cool 2 - shinenrise

[ArchivalUser]

A 55-year-old man is being followed by his primary care physician for hypertension and cardiac disease. The patient has been on several medications in the past with sub-optimal results. The physician considers adding verapamil to the patient’s regimen, knowing that verapamil can be used in patients with arterial hypertension due to its vasodilatory properties. Verapamil also affects cardiac contractility but has a minimal effect on skeletal muscle. Which of the following properties of skeletal muscle is responsible for its resistance to the effect of verapamil?

A. Calmodulin-independent excitation-contraction coupling
B. Elaborate T-tubular system
C. No dependence on extracellular calcium
D. No internal automaticity
E. Troponin C affinity to intracellular calcium

[ArchivalUser]

Is it A?

[ArchivalUser]

cos i think calmodulin is mainly smooth muscles

[ArchivalUser]

C ?

E. Is for smooth muscle and smooth muscle is calmodulin depend not indrpnt.

[ArchivalUser]

yh you might be right anastep on a 2nd look

[ArchivalUser]

Ccc

[ArchivalUser]

yes C is the correct one!

skeletal muscle is independent of extracellur Ca++ ,while smooth and cardiac muscle do.therefore verapamil drugs act on them not skeletal muscle.(calcium induced ca release)