The following statements concerning
the mechanism of calcium channel blockers
action are true, EXCEPT:
Answer
A. Therapeutically active agents in this
group are capable of releasing nitric oxide
(NO) in vascular smooth muscle target
tissues
B. Calcium channel blockers bind to L-
type calcium channel sites
C. Calcium channel blockers useful in
angina decrease myocardial oxygen
uirement (by decreasing the
determinations of oxygen demand) and
increase myocardial oxygen delivery (by
reversing coronary arterial spasm)
D. Calcium channel blockers decrease
transmembrane calcium current associated
in smooth muscle with long-lasting
relaxation and in a cardiac muscle with a
reduction in contractility
Answers
Answer:
if you have angina (chest pain), high or low blood pressure, and an arrhythmia, your doctor may prescribe a calcium channel blocker. these drugs dilate your blood vessels. this allows more blood to flow to the heart, which helps ease chest pain and decrease blood pressure. these drugs can also slow your heart rate.Calcium channels regulate contraction. When an action potential travels down the surface of a smooth muscle cell, calcium channels open and calcium ions flow inward, initiating the contractile process. If calcium channels are blocked, contraction will be prevented and vasodilation will result.Calcium channel blockers lower your blood pressure by preventing calcium from entering the cells of your heart and arteries. Calcium causes the heart and arteries to contract more strongly. By blocking calcium, calcium channel blockers allow blood vessels to relax and open.