Presentation of Muscle action potential from Guyton and Hall physiology chapter 7.

1. MUSCLE ACTION
POTENTIAL
PRESENTED BY
AMNA IMRAN

3. Definition
 The wave of electrical potential which passes across a muscle is known as muscle action
potential

4. Quantitative Aspects
 The procedure is same as that of neuron action potential.
 Muscle action potential differs in quantitative aspects.
In Muscle action potential,
•- Resting membrane potential is about -80 to -90 millivolts.
•- Action potential occurs for about 1-5 milliseconds.
•- Action potential conducts at a velocity of 3-5 meter per second.

5. Excitation contraction coupling
 The muscle fibers are large and action potential cannot panetrate deep inside
each myofibril.
 Muscle contraction requires current to panetrate deeply into vicinity of each
myofibril.
 It is acquired by TRANSVERSE TUBULES.
 T tubules release calcium ions inside muscle myofibrils.
 Calcium ions ultimately causes contraction.