1 Muscular System Overview Skeletal Muscle Cardiac Muscle Smooth Muscle.
Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students...
-
Upload
nguyenduong -
Category
Documents
-
view
216 -
download
2
Transcript of Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students...
![Page 1: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/1.jpg)
1
Cardiac Muscle
Physiology
Faisal Mohammed, MD, PhD
![Page 2: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/2.jpg)
2
Objectives:
By The end of this lecture students should be able to:
Distinguish the cardiac muscle cell
microstructure
Describe cardiac muscle action potential
Point out the functional importance of the action
potential
Outline the intracellular calcium homeostasis
![Page 3: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/3.jpg)
Wall of the heart
Cardiac Muscle Cells
![Page 4: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/4.jpg)
![Page 5: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/5.jpg)
![Page 6: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/6.jpg)
![Page 7: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/7.jpg)
7
Permeability Changes and Ionic Fluxes During
an Action Potential (skeletal Muscle)
![Page 8: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/8.jpg)
0
12
3
4
![Page 9: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/9.jpg)
The Action Potential in Skeletal and Cardiac
Muscle
Figure 20.15
![Page 10: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/10.jpg)
![Page 11: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/11.jpg)
11
![Page 12: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/12.jpg)
12
![Page 13: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/13.jpg)
13
![Page 14: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/14.jpg)
Functional importance of Cardiac
action potential
The decrease in conductance (permeability) of potassium at phase 0 and 1 of the cardiac action potential contributes to the maintenance of depolarization in phase 2 (plateau)
The long absolute refractory period prevent the occurrence of tetanus (maintained contraction without a period of relaxation) in the cardiac muscle.
Skeletal muscle action potential is short that allows tetanus to occur
![Page 15: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/15.jpg)
(activation gate) m Gate
(inactivation gate) h Gate
Activation gates open when the membrane potential
becomes less negative and the inactivation gates close
when the potential becomes less negative. The activation
gate is fast but the inactivation is slow responding
![Page 16: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/16.jpg)
16
PHASE 0 OF THE FAST FIBER ACTION
POTENTIAL
h
m
Na+
-90mv
A
Na+
mmh
-65mv
B
mh
Na+
0mv
C mh
Na+
D+20mv
Na+
mh
+30mvE
Chemical
Gradient
Electrical
Gradient
![Page 17: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/17.jpg)
![Page 18: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/18.jpg)
18
The importance of calcium influx through the
slow voltage gated calcium channels
![Page 19: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/19.jpg)
Mechanism of Cardiac Muscle Excitation, Contraction & Relaxation
![Page 20: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/20.jpg)
20
Intracellular Calcium Homeostasis…1
![Page 21: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/21.jpg)
21
Intracellular Calcium Homeostasis…2
![Page 22: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/22.jpg)
22
Cardiac Muscle action potential Vs.
Skeletal Muscle
Phase 0 –Depolarization phase (Na+ influx)
Phase 1 partial repolarization (Not in
skeletal)
Phase 2 Plateau (~ depolarization not in
skeletal) slow calcium channels
Phase 3 fast repolarization phase (K+
repolarization()
Phase 4 resting membrane potential
![Page 23: Cardiac Muscle Physiology - · PDF file2 Objectives: By The end of this lecture students should be able to: Distinguish the cardiac muscle cell microstructure Describe cardiac muscle](https://reader031.fdocuments.us/reader031/viewer/2022022505/5ab9a1c27f8b9ac1058e1a91/html5/thumbnails/23.jpg)
23
Thank You