Which of the following statements concerning potassium channel openers is true?

A. These agents decrease transmembrane calcium current associated in a smooth muscle with long-lasting relaxation
and in a cardiac muscle with a reduction in contractility
B. These agents has a moderate reflex and vascular dilative action caused by the stimulation of sensitive nerve endings
C. Beneficial effects of these agents are related primarily to their hemodynamic effects – decreased heart rate, blood
pressure, and contractility – which decrease myocardial oxygen requirements at rest and during exercise
D. These agents increase the permeability of K channels, probably ATP-dependent K channels, that results in stabilizing the membrane potential of excitable cells near the resting potential

Submitted by: Dr.Tassawer-e-Meran

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