Nitric oxide augments Ca2+-dependent K+ currents in the human radial artery via a cGMP-independent mechanism, suggesting K+ channel activators may help prevent post-surgical vasospasm.
The radial artery manifests mainly Ca(2+)-dependent K(+) currents at rest; this current is augmented by nitric oxide through a cGMP- and protein kinase G-independent action. The relatively depolarized membrane potential, as well as its muscular structure, predisposes the radial artery to spasm. Agents that activate the Ca(2+)-dependent K(+) current could be of therapeutic value in preventing post-surgical vasospasm.
Zhang et al. (Mon,) studied this question.