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Signing on it
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Welcome thank you for having a good night so far and things are going well at least we can get that book and that's what we need we need to have access to that book
OG Mary would come through Mary is awesome Mary Lawson
No it's Tuesday so that means that somebody reminded me it's Tuesday that means go
Mardi Gras in New Orleans for a few years they have Mardi Gras in Mobile as well so that was that was Tuesday's Gone
Boutonniere
X-Men
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About to do a little EKG reading little EKG reading that's where we finished off so let's do a little EKG reading now I want to remind
What time
Step 1 Step 1 is not about being a resident in cardiology all right it is not about being a resident in cardiology be basic EKG
7 kg at all okay it's not the highest of you but we will go through it because we're shooting for the stars on the exam
So we're going to give you the fundamentals of the EKG so we're going to do basic aspects
EKG is recording of the cardiac action potential that's a voltmeter so on the y-axis
On the y-axis
260 and greater
On the y-axis is
Technically one big box is half of a half of millivolt but I would not I would not worry about that on Step 1 but you do need to pee
The fact that the x-axis is time
Until one big box and a big box I mean frumpy line for heavy long is .2 seconds
There are subdivisions within that so that each small box or 5 subdivisions to eat small box is .04
Sex
And we do have to have some sense of the time okay some sense of the time
Or the fact that the x-axis is time
Alright so here's a classic look from lead one of the first things were going to do one of the ways I want to show you real quick
What you want to do here's how I would approach EKG on Step 1 is actually would apply to step to to some degree but for Stuff
Very quick because we only have a limited amount of what we want to do is the first thing we do is we qualitatively look at this
And say is there a steady Rhythm and by a steady Rhythm or the East always about the same distance apart
Alright so you could say the same about a steady rhythm in this
Do you see a steady rhythm
Okay we will talk about you can
The RR interval the faster the rate
300 150 175 6051 looking for 300 quick
365 boxes is one second one second
375 looking forward to
Next thing that you do you determine qualitatively examine the waves look like this
Wanted to
As we go through the arrhythmias that you're most likely to see that you're most likely to see they're going to involve most of the
Alterations in the Paranormal so I can do Rhythm and rate
I think qualitatively examine the waves to make sure I can see him
And then jump right in and quantitative the PR interval
What I'm going to do is a blow-up of that area
So each little box is .04
Each big box at any line is .2
Now the normal PR interval is .12
.21
Which means which means three to five little boxes three to five little boxes
That's what we're looking for 325 little boxes so I started here I got one two three and a half
Approximately so it's normal if it's between three and five little boxes that's a normal PR interval
Three little boxes is 120 milliseconds 5 Little Boxes is 200 milliseconds you just start at the start of the P wave
How do you hit the always 1234 so between 3 and 5
Here's the start of the P wave
Is the ER so I just count the boxes
1
2
Three and a little more so it's between three and five we're good
Again between 3 and 5 boxes is a normal PR interval
So that's the next step I would do
Because a lot of these are really going to show up related to the PR interval you will see
So I guess quality we determine Rhythm is a steady Rhythm if so calculate the rate
Then do you find Peter St Peter St and do they look okay
And then I want to take the PR interval
This basic steps texting very good overall EKGs even if you progressed past Step 1 for Step 1 this should work that should work
I'm saying that it starts on this line and the r-wave is starting her
Waiting this box in this box
It starts here where my arrow is so one two three and a half
Oh okay starts with the p that's what they are on the floor that's where we start
At the start of the P wave
All right now the other thing you want to do is look at me and electrical axis
The mean electrical axis
Now this is another one where you can get very precise but you won't need to on step one we're going to do a shortcut
We're going to do what's called the quadrant method
This is a shortcut to tell us if the mean in electrical axis is normal mean Electro electrical axis is the net Direction
Ventricular depolarization zombie QRS complex
U.s. complex
Always remember this is imagine that it's on my chest you're looking at it on my chest
So this is left
This is my right
Normal range for mean electrical axis is -32
Shortcut we're not going to go through all the physics of it but trust me the physics work out the physics work out
We're going to take to delete
We're going to take the lead one which is your horizontal lead
Lead one is your horizontal lead with the Positive end of the terminal on your left arm
Are they going to take a nap
ATF goes to the foot
So it's your vertical leap to notice what we're doing where is all the lead vertical leap
And by doing this by looking at these two leads only these two leads we can determine what quadrant the mean electrical axis is in
Here's the setup
If the mean electrical axis shows up here that's normal if it does he remember you're looking at me so it's my left side
What axis deviation
If it's over here then we have a right Axis deviation
South Texas Texas
Now how are we going to determine this way all we have to do is determine the net deflection
In the QRS complex for Lead 1 and AVL Lead 1 and avf
I would get I would if you get an EKG on your exam I would determine the mean electrical axis absolutely
Alright so we're just going to look at least one we're looking at a VA
Cutting through or cutting through
All the physics behind it alright to what we're going to do is qualitatively determine if the QRS is not positive not negative
Autonet deflection I'm about to go to that new shoes okay
So here we go I'm going to show you a picture it's not there but I just want you to look at it
And when I say that deflection you consider the up -
So up - down
If it is more than that it's positive
If there is more than enough then it's negative if they're the same then there's no way I'm going to show you pictures and I want you to know
Alright I want you to tell me is the net deflection positive negative or no net change
Here's the QRS complex
We find the shape of a point is right here
Do you have more going up or going down or is up and down the same
You have more going up is it positive negative
Somebody that is more going up a problem just curious
Positive reflection and I know this is so from this point I look at how much it goes up
This has more than one going down there
What's this
Excellent I have a lot more going down the going up
This is a negative deflection negative
What's this
There's no difference in the same
Positive positive between 0 and 90
Good
To the left side
Quadrant which corresponds to left axis deviation posterior bundle branch is bundle branch
How do you say this
Determine the deflection
If they're both positive you have a normal axis
If a test is negative and one is positive you're over here
Current Direction has moved
And again the big ones to look for on step will be left ventricular either I purchase for your dilation
All right now
Is positive and one is negative
Then the main axis is between 90 and 180 which means it's in this quadrant
That is a right Axis deviation
This year we are looking at the net deflection and 80th for the QRS and the net deflection in Lead 1
So that's what we're looking at that you determine is it net positive or negative
Yes baby I figure it's got a positive and a negative Lead 1
ATF is part of the lead on the EKG you better have 12 leads on the EKG 1 2 & 3 AV Lab Rats
And then you have six Precor tables
So leave one negative a positive
Squadron right Axis deviation
And they're both negative
If they're both negative
Causation
Right ventricular conduction defects or the posterior left bundle branch cause remember the posterior left bundle branch did not call
Election poster left bundle branch causes
Axis deviation
And left side in my unless the left ventricle dialing cuz remember if the left ventricle dilate
If the left ventricle dilated
Then I will pull it to the left
When you get a conduction block it takes time for the for the current to go through okay it takes time for the current to go
Round
So what that doesn't slow it down and it pulls the electrical components of What's called the factor
Okay in that direction
So I am really come by passing without going into great great detail that's the best I can do I can't go into great detail but it take away
You take way too long and it won't be hurt you whatsoever for Step 1
But bottom line you're changing how rapidly things conduct that changes to the electrical current
And that's what causes a deviation
When a BF and leave one or both negative then you still have a right Axis deviation you're over here so no to something
If you have a negative negative lead one you're going to get a right Axis deviation and I wouldn't worry about extreme right Acts
Right Axis I wouldn't even worry about it I wouldn't even worry about it
Not for Step 1 I wouldn't
Okay so again are you doing this
Cause of extreme right would be some significant conduction defect is most likely but again I wouldn't worry about it
This is going to work is it a right Axis deviation
They might get it with cor pulmonale with extreme hypertrophy of the right ventricle
But all of these are going to shift to the right so if you have a negative lead when you have a right Axis deviation
Okay maybe you're giving examples you're absolutely right corner right ventricular failure pulmonary hypertension that causes high
Absolutely absolutely
Gay is the way there's no not know yet depends on which one we're talking about
If there's no net deflection then the main axis is 90 degrees
Let's say lead one has known that I look at a vehicle if it's positive that I'm right here at 90 degrees
Still normal still normal
If a BF is negative that I'm up here I still have a left axis deviation
Gay
This is a quick quick quick method very quick
And all you're doing is looking at ATF lead one on a 12-lead EKG
We don't have any we don't have any 12 lead EKG examples in the book
That's why I gave you those basic that's all you do is find 180th and look at the net that we went through
Just want you to know whether or not there's an axis deviation phone number words they make clothing in the clinicals in
Until they said patient X has a right Axis deviation on the EKG and you go right Axis deviation that's over here
What could cause that well whatever could cause hypertrophy of the right ventricle and the pulmonary embolism or pulmonary
Cor pulmonale all those kinds of things but that's just too cute it's just too cute or they may give you an EKG where you're looking
No this patient looks like they're having heart failure and they give you a 12-lead EKG
Right Axis deviation you know it's right heart failure not left heart failure
That's how they're going to play it that's going to be kind of the clinical vignette scenarios
So that's why I would if they give you a 12-lead EKG
Do it real quick look at one look at a VA bingo
They may give you a question about axis deviation absolutely like I just said
Get it excellent excellent let's go to some basic arrhythmias if you're going to see a rose on Step 1 these are Far and Away the
Clearly these are all things that exist
But again this is not super high yield for Step 1 basic very basic Step 2
Maybe
What we're studying for Step 1 right now we're not worried about that
The first let's go through all the heart blocks is an example of first degree heart block do you see a steady rhythm
Very good we have a steady wear them so we determine the rate
Here we go 300 150-175 almost 60 the next our way this is just a little before the box so heart rate is normal it's between
Is between 60 and 100
The stadium
Have a great Next Step do I see purse first post Next Step The Next Step
What are you jump to next exactly jump right to that PR interval
Start of the P wave
The QRS complex in this example is 8 boxes of boxes
It's much greater than 325
How much greater this is by definition first degree heart block first degree heart block is elongation of the PR interval
The Beatles greater than one big box
This is first degree heart block
Patient doesn't have bradycardia heart rate is normal it's just a little above 60 have a normal heart rate
We have a normal heart rate
But we have an elongated PR interval we are having problems connecting to the AV node
We are having problems connecting to the AV node
Could be damaged
Email for example for example
Alright next now your book is wrong so please correct it this figure should say second degree heart block
Alright 2nd degree heart block
Calcium channel blockers and beta-blockers
Exaggerator first-degree block
Because they're going to slow conduction through the AV node
Nice question to you
Alright please correct your boat 2nd degree heart block
Second degree heart block
Sorry about the typos all right first thing we do you see a steady rhythm
You see a steady rhythm
No I'm steady Rhythm so one of the things to think about with an unsteady Rhythm is a second degree heart block
But this example of Winky Bock have an unsteady rhythm
UIC sdn sdn do we jump to next
Where do we jump to next after we've qualitatively look PR interval okay let's start with this one there's a PR interval
Man it's getting longer getting longer getting longer wait a minute there's a piece and no QRS and my PR interval comes back
Let's go over here
PR interval getting longer getting longer P wave no QRS
What is mobitz type 1 Wiki bar there is a progressive prolongation of the PR interval and tell him ventricular be dismissed in the
Again
Here we go
This is the definition of second degree heart block
Free QRS is preceded by
But not every P wave is followed by a QRS
Gave notice
Every QRS is preceded by a
Not every piece is followed by QRS that is the definition of second degree heart block
We have two types mobitz 1 mobitz 2 but which one is winky Bock winky Bock is a progressive prolongation of the PR interval
Till we drop the beat
And then it starts over that's why he bought so I'm steady Rhythm while the first arrhythmias that should go into your head thank you bye
Winky bock
Now let me ask you this what I said last night
I said where's atrial repolarization where is atrial repolarization and you told me it was buried in the QRS right you said
Because it's buried in the QRS
There's a way there's no cure and buried it
Do you see atrial repolarization
Here's the P wave no tequila
Do you see a jewelry party polarization see the EKG doesn't pick it up because he doesn't pick it up
Haha I told you I would prove it to you told you I would prove it to you but then you're going to go well you know I'm still not
Not convinced I'm going to do on the next slide but first
What you need to do at the break or after the lecture is over is go to YouTube and search for diagnosis wenckebach you will love
You will love it I promise I promise not now
Here's a real EKG real person winky bock
P-wave know you are
Do you see atrial repolarization
P wave Nokia
Atrial repolarization depolarization
Dkg can't pick it up he doesn't pick it up you can pick up tons of heart blocks have p waves
And there's no atrial repolarization
Gay
You don't pronounce it winky bock
That's how everybody I've ever talked to
This would be a negative deflection
German USA
Type 2s
Rules are rules every QRS is pretty but not every P wave QRS
Okay going to distinguish and weak
Reebok
Exactly when you have a PR interval
It will be the same
Winky Winky Bock changing that's how you distinguish all right now could be onstage Justin can go with that okay
How we distinguish them
Is the PR interval exist
It will be the same and mobitz type 2 it will not be the same week
See where we're going to that.
Number to see if it's pretty much the same
370
Well then that's weird that's weird I mount a hard time finding pqrst are you having a hard time finding P QRS t
Are you having a hard time
No not at all I am it's kinda hard to see
They're there if you want to know if you want
But don't spend time here's the point don't spend time trying to label every P wave it's not going to get you so I'm going to help you
You're having trouble finding Pedro St that sends a signal in your head
That sends a signal in your head
Steady wear them saying that slow where is that PR interval
Time finding another animal the reason because the Atria have a certain rate in The ventricle has a different rate complete
Atrial ventricular not talking to each other they're not talking to each other completely dissociated but you don't have to go
That's not the point
3rd degree heart block
Ventricular rate is usually slow this is a tough arrhythmia to get but if you do this little message you'll get it you'll get it
What steady Rhythm and slow start thinking third degree heart block
Steady Rhythm that's low and slow
33 harbuck confirm I can't find a nice Loft PR animal Bingo 3rd degree heart block be no that's what do Emerald again
Big heart but
Unfortunately what students typically do if you're spending so much time trying to figure out exactly where every P wave is
You wasted 2 minutes on this question which you don't want to do you don't want to find just look for
Steady Rhythm that slow I do not see a lot of PR interval 33 hard but I think that's the answer move on
That's the answer move on
That's your answer
Third degree heart block you get the answer right you're wrong you're not spending all that
All right we'll finish this and then take a break don't worry about
First thing we do
Okay so we exclude
Next 360 waves
Looks like
This is a very very coordinated conduction
So that's why we see these waves in his coordinator almost always have them
I'm pretty sure
What's up with that
No coordination
In between the QRS and T
There's no pattern whatsoever so unsteady Rhythm winky Bock moments too maybe even a fan
I like it I like a 57 a father I wouldn't be surprised if you get an EKG hmm yeah yeah I like that
There's no coordinated conduction that's why we don't have anything resembling a p-wave
Atrial flutter is almost almost a hundred percent of times that you have to appreciate on a EKG
It's really difficult to say a hundred percent
Okay but I wouldn't look for that you know if you hear hoofbeats horses so atrial flutter going to be studying step one it's going to be
Cuz it's almost always daddy almost always
So rare that it's not
The last one is called Wolff Parkinson White
Wolff Parkinson White disease
Safeway Atria to the ventricles
Okay
Which one are you referring to exactly
This one is they feel unsteady Rhythm can't find a p-wave
I'm steady Rhythm can't find the P wave AFib
Next question just move on you gotta move on
Wpw do you see the steady rhythm
UCSD wear them
Yeah we still good
Determine the rate 300 150-175 okay okay okay right
Do you see pqrst pqrst
Us the best post
What's good what's the next thing we do
What's the next thing
You are exactly right to that. It's this isn't
Best sample does this is about three black boxes so it's on the short end but the other distinguishing feature here is notice
Get this slow enough you don't normally the P wave goes and then flat and then are this is a Delta wave
This is a beautiful example of the delta-wave right there
Incidentally this is the
Short PR interval and the delta-wave double
Accessory pathway for me to add event
Short PR intervals telling you you don't have it again PR interval
All about AV node delay here with bypassing it or bypassing the AV node
Right here this right you know the P wave ends and then it starts Rising you start seeing the way he always
Again the P wave normally after the end of the people we have a
Then it shoots up here the end of the p-wave it start
Running above our ways that that's the delta-wave
And you're concerned about this arrhythmia taking if they go into a tachycardia
Alright for the very last part then we'll take a break will end up the EKG and take a break
Here are some high-heeled things to
From Step One related related to changes in the EKG OK some paths Farm integration ST segment elevation
Transmural infarction
I need to cross the Wall
And prinzmetal angina
Which is corn a face spasms this is real important for pharmacology folks right here
This is prinzmetal angina so you think this is spasm
If the ST segment gets depressed
Give it to me and I do you know antidepressant agents
Valium something like that it's really depressed it said it's okay sorry
This is a classic sometimes called exertional sometimes hold stable angina
Gave this again is very high yield for pharmacology
All right now potassium calcium very important
Hyperkalemia will increase the rate of repolarization hyperkalemia will increase the rate of repolarization you made it this real quick
Who invented the presents you give me the prices to the SD yes he is really depressed if he is depressed to see how depressed you
So you give it to any depressants
The joke
Hyperkalemia increases the rate of repolarization that's the T wave
Looking for Sharp spiked T waves that suggest hyperkalemia
This would decrease the QT interval because I'm repolarizing faster
Right now what we talked about for potassium and calcium in nerves doesn't apply to the heart so don't try to figure out
See how this works
You just gotta roll with it this is one of those you just have to roll with this is changing potassium Channel function
Going the other direction
Bulimia hyper increased it hypo will decrease it and we can generate what are called waves which are secondary waves after the T
Alright secondary waves after the T wave
So you get the waves in hypokalemia yeah if I'm delaying repolarization than the QT interval gets longer
The QT interval gets longer
Alright remind me of the antiarrhythmics are going to have the same effect
Antiarrhythmics
Affect
Class give me the classes are very good one day
And class 3 good class 3 anti-arrhythmic stupid
Channel blockers Smurf drug sotalol
And also the one the one okay that's quinidine and procainamide why do we care about a Long QT
Why do we care about a Long QT you don't have the pictures I'm just showing you the pictures I'm just putting the text on the picture
I'm just putting the tax in Texas right there I'm just following along with the text beautiful you worried about this one
You worry about this potentially fatal arrhythmia course I'm very high yield for step one right here Long QT increases possibility
Very high heels very high heels I'm just trying it on this picture to show you
The text is right there we're just following the text we have been a little ride here because we wanted to integrate some Farm
Reminding reminding
We understood Moses weekend remember you
Linda genetic sodium channels that don't activate that's what we talked about last night Miguel very good very good
Tree with magnesium you're right
Alright last is calcium
Calciums going to work just like the potassium if I have too much calcium decrease QT interval if I have too little calcium
Creepy animal just like potassium hyperkalemia hypokalemia again do not do not try to apply what we talked with the nurse
This is different and what I would look for all these is it written in the clinical vignette
What do you mean the books
Thank you for pointing that out we gotta fix that
Is it wrong wrong
I was there when we come back we'll do a little something move onto skeletal muscle will take a break there
Thank you for pointing out the error
Let me rephrase that let me rephrase that 20 out the error error who did that who had
Good good
Going to get a cookie for that
What
Okay we are back
Mommy I'm saying correctly
Close enough I'm sorry I'm doing the best I can
I'll bring you a cookie
Let you down I would let you down
Well good I like it when we're energized there we go what we're going to do before we go to the next chapter
Weird question
So we close to here
Could increase the calcium current but we're looking for a decreased RR interval funny current that's so damn crazy star
Correct answer is 3 you all did very well very well alright glad you're all refreshed
Alright good job on that one
All right now we're going to do is we're going to move from the electrical activity and start thinking about mechanical
We're going to start with skeletal muscle all right skeletal muscle excitation contraction coupling
Alright here's the basic Ultra structure of a skeletal muscle myofibril
Cell for skeletal muscle is composed of all of these sarcomeres still here still functional unit the sarcomere right here is the
I wouldn't get too bogged down on its own a band I band excetera
I don't think they're really going to press you on that on step exam but you do need to pay attention to is the idea that
Where is the functional unit of the sarcomere is the functional unit
And then that's sarcomere this portion we're going to have actin filaments that's here myosin filaments is here and then we're all
Another protein called Titan titans going to be important because it holds onto myosin alright it holds onto myosin part of the Atlantic
Yeah we're about to go into a love story this is a love story I'll show you in just a moment but he recovered just a spectator
Sear functional unit again actin myosin hiking
Now
Remember that the cell membrane is called a sarcolemma sarcolemma for muscle so there's your myofibrils within the sarcolemma
The T tubules is just an extension of the sarcolemma it will dive down there and this will be important because it will carry the axe
Take care of the action potential from the sarcolemma down into these myofibrils
And last but not least the terminal cisternae this is of the SR sarcoplasmic reticulum its stores calcium
It's store
Five basic proteins that we need to know for Step 1
And it turns out it's a love story love stories I hope you like love stories do you like love stories are we good with love
Are they okay because you know we get a little sappy it's okay it's okay it's love story
This is the kingdom of striated muscle
Okay the kingdom of striated muscle so this will apply to cardiac and skeletal we're really just referring to skeletal but it
Kingdom of striated muscle in his kingdom of course we have the beautiful princess named acting she is so pretty very beautiful prayer
And she's in love with a handsome young prince niacin here's my sis is the myosin head actin and myosin really really really
I mean they love each other
And turns out that acted as a binding site for myosin
We're trying to do
Because
The king of the land and who is his daughter
Covers
What's going on
Is the jilted Lover of My Soul
The whole time the whole time
Go to your
221 graduate college recent ones in college not married no kids no grandkids
Did you ever read stories to my children like this yeah
Anyway what was I talking about this but it's just the picture and wants to bind to actin now I know this is hard to believe
Medicines in a high-energy state
SNSD TTS
It's hard to believe that out there who's in love with a young woman and he has a lot of energy for her I know that's a stretch
I try to work with me work with me
Madison high energy State because Mason has split ATP high-energy State ready to go where Acton Acton wherefore art thou my Acton
Yes it is ready to go ready to go high energy
Stay away from my daughter stay away from my daughter got it prevents the interaction
When calcium prices in the cytosol well thank
And look at another two lovers so what do they do
Hug a pug
G-rated
And it's a very forceful tug how many miles is in a high-energy state
Love of his life he grabs his acting and poser poser which of course is referred to as the power struggle but it's just a hug
Gator pulling his acting generates Force that's called the power stroke that's what generates force in muscle this binding of a
Generates Force generates Force
Take this picture but I'm thinking on the myosin head tightness and in this picture but I just reminded you tighten sagging on the bus
Now the king is no dummy the king is no dummy
So he has a bunch of little minions because he's the king called ATP and what is ATP it goes It goes pushes them apart
You can play
What does Niacin do
Which puts it into a high-energy state
And back he goes to acting as long as acting is available they bind and hug and he pulls in ATP comes and Associate Sweet Shop CT
High Energy stadium
Acton phone bison call that's cross Bridge cycling that generates active tension in this process just keeps going provided
Calcium calcium is the key and it's troponin that binds to calcium
So let's think about something for a second think about something for a second
The quicker the quicker myosin can split ATP the quicker you can get back to his love do you agree
Think about that
The faster myosin can
TP the quicker he gets back to his love
So the faster the ATP Ace activity the faster we we bind and the faster we took we took acting
So I will talk about in just a little bit the velocity of shortening is directly related to the ATP Ace activity does the fast
Faster I can do that
The quicker they can get back together
Tell him I said he's a big player in determining velocity
182 put some ice in a high energy state in number to OC Tech
Around
Animal hug for a very long time
When do you not have ATP
Why would you not have ATP
Rigamortis
And that's because actin and myosin her hugging tight they are hugging tight
And they're not going to let go that's Rigamortis
But let's think about something else that's not for a moment yeah he's awesome he's awesome remember
Do we remember most about it I'm sure you talked about it
Deficiency
Alright alright
And then
Because they can generate sufficient quantities to dissociate actin and myosin and that muscle locks up very very similar
Sports
They don't release lactic acid the doctors talk all talk about that
Dr. Circle
I'm sure you told you sure you told you yes but they won't release lactic acid and that's one of the Hallmark traits and mcardle's
So I clinical exam stress test just contracted muscle and they develop contractures and it's noted that venous blood does not have a
Lactic acid Bingo Cardinals
Physiologic contracture with no lactic acid Bingo the Cardinals that's a mcardle's patients a little quicker without doctor
It reminds us of dr. Turk
What an awesome awesome instructor
Once we get calcium back to a low-level trouble by
Tropomyosin gets back in the game show up on my ass and gets back in the way
The patient doesn't have to be very young I mean you make diagnosis when they're young but you can live there are patients with my car
Are certainly in the adult phase certainly adults they don't have to be very young although that's probably when you're going to do
Yeah they can get muscle injury so they may get a little myoglobin in the urine okay with the doctor
He's about chemistry Guru
But it makes sense
Contractures if I can make a teepee
Clearly said Kelsey music goes back down compromising comes back and gets in the way no more interaction for r4r
Two young lovers
Since calcium is the key next step for Step 1 is that we need to know as well how do we regulate calcium
Well that's life
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Receptors and we need to think about that one is the Hydro pyridine
Oh dear he's resting skeletal muscle Hydra parody
The Hydra pyridine is all
Lambo membrane right here it's on the membrane of the skeletal muscle cell
So it's associated with the sarcolemma
Technically the HP or voltage-gated calcium
Can calcium channel
Technically technically okay however calcium does not flux through the channel in skeletal muscle it will in cardiac it will end soon
Doesn't in skeletal
So what you doing in skeletal it's acting as a voltage sensor
Hey it's acting as a voltage sensor
Cuz it's a voltage-gated channel
II receptor is right here or why are Ryan Daddy
Vanity
Everest
Tide recruiting is going
Diana t
Sonos PHP part of the sarcolemma
Fits into the rioting Channel ryanodine receptor Ryan any news on the sarcoplasmic reticulum
It's a calcium channel on the sarcoplasmic reticulum so the two big things for calcium skeletal muscle Hydra.
Voltage sensor
Diana Dean calcium channel on the Sr
Look at the picture the picture remind you
You have a lot of calcium inside the SR so you have a big gradient for calcium come out of the SR into the cytosol why doesn't it
Because BHP blocks the Ryan
Dhp blocks and here's the way to think of it there's way to think of it look at it it's like a cork
In a champagne bottle
Or wine bottle BHP at rest is cooking it's working
The reality Channel
Hey it's corking the reality Channel
Everest
So therefore calcium doesn't come out through right now because it can't it is physically blocked
Sewing skeletal muscle dhp physically blocks the Rye ending it works it so we're sitting right there pork in a quart
What happens when we initiate an action potential
Where's the neuron releases acetylcholine onto what receptor on to what receptor
Silicone injected on what receptor
Nicotinic muscle very good nicotinic muscle produces an Epp you're right Maria very good
Generate an action potential but it's a nicotinic on the muscle very good non-selective something important
Action potential is carried down the membrane by the fast channels in Dives down into the cellar
What channels carry the action last night
O2 sensor
Simpsons change in potential
Change and what happens here is the action potential coming down it causes the HP to change confirmation
Ensure and Uncorked and uncorks Ryan daddy so it's just like taking and going
So the action potential pop the cork for Ryan today
When we pop the cork for Rite Aid in calcium was going to move down its electrical gradient we're going to flood the side of
No notice we pop the cork
This calcium the comes out will open other Ryan adding channels
This is calcium induced calcium release
So calcium in during the cytosol opens other Ryan today which will cause more calcium release calcium induced calcium
Peace
Member we mention that last night with cardiac muscle have the exact same thing here at the exact same thing here but what's different
Calcium is coming from the Sr
Calcium
Binds to troponin hey can we get cross Bridge cycling active tension
So that's how we can regulate or that's how we release calcium in the action potential
Incense by dhp it on chords Ryan Adams
Some of the excess calcium opens other Ryan D calcium induced calcium release
Calcium binds to troponin C this causes crossword cycling that's muscle contraction active tension
All right now
ATP is called Circa
Circa is a calcium ATP a step pumps calcium back into the Sr
And once we pump enough calcium back into the Sr
No more hey Jeannie
Tropomyosin goes back and you get relaxation
So what drives relaxation Circa activity Circa activity Circa is responsible for relaxation
Correct Monica calcium released from the SR triggers more calcium released from the SR by opening Randy that's calcium induced
Circa pumps the calcium back yet that's how we get relaxation
Alright keep on
We got a contraction one side of Salt Lake County
Once we pump it all back in you get relaxation it's all related to calcium
Circa is an ATP AC pump calcium against its electrochemical gradient
It's a pump basically a pump
Not all calcium for contraction of skeletal muscle comes from the Sr
Calcium for skeletal muscle contraction comes from the ass or we're not we're not moving here from the extracellular compartment
Are all coming from the Sr
No sign of Salt Lake Council is responsible for contraction in skeletal muscle you do not need cytosolic calcium
For the mechanical effects of calcium affect the nerves
But you don't need it you don't need it it's different for smooth and cardiac you're absolutely right and will mention those and and
When you pop it back in then go yes
Voltage-gated sodium
Carrying the action potential just like in a nerve
They are responsible for the action potential
Muscle relaxers work on Circa not to my knowledge
Most of those work Central 82 all turn around I'll put most but I don't know tons about those
We can have questions from like this as well give up we'll do some assessments at the end but you know we can frame questions in a
Remind me ourselves of Circa so let's say somebody can't relax very easily so he got a patient may fail to show normal muscular
Versation
The problem is defined in the muscle itself you should be looking for circa Circa as your answer
Right there two ATP is involved in the myosin ATP Ace we already discussed cross Bridge cycling and Circa and Circa
Circus themes for smooth endoplasmic reticulum calcium dependent a GPS or something like that in your book it's such a long thing
Do I have to pay
What the actual word he is in the boat
Sarcoplasmic in the number 760
ADHD defect would not cause a problem with relaxation
Okay so those are steps again closed
Cork we record an action potential and corks
Calcium channel blockers do not affect skeletal muscle
That's why the Hydra.
Candles don't affect skeletal muscle because no calcium is going in no calcium is going in through here we go
Okay they do affect smooth and cardiac but not here because calciums not flexing calciums not flexible path Farm integration
Hyperthermia
Malignant hyperthermia is the opening of ryanodine receptor stimulation and Aesthetics like how the thing but also sucks and Elk
You get hyperthermia because you're driving cross Bridge cycling these are staying open calciums around our lovers get the hug
Hug and hug and hug and break and hugging you generate heat hence the hyperthermia
If you beat me to it Angela you treat with
You treat with dantrolene why do we treat with dantrolene because it blocks
Ryan Adams blocks Ridin Dirty
Why don't you just use rocuronium
I mean it's such a cool drug such a cool name why don't we just call it rock your world when we just do some rocuronium
Too much hugging you're right I put them in for too much onion
Why don't you just use rocuronium work work
Because you're right it's blocking up here
It's not going to do anything to this because we have a direct opening of these by these compounds
The Rocky Mountains not going to help we have to do something at the site which is a receptor that's why they're doing is working
Excellent we'll take a break there when we come back
We'll talk about how we can change force in skeletal muscle