Key result
Cilnidipine dilated both arterioles and venules in hamster cheek pouches, whereas nifedipine dilated arterioles alone, demonstrating the role of N-type calcium channels in venular dilation.
Why the study?
Does cilnidipine (an L+N type calcium channel blocker) dilate venules differently than nifedipine (an L-type blocker) in hamster cheek pouches?
Does cilnidipine (an L+N type calcium channel blocker) dilate venules differently than nifedipine (an L-type blocker) in hamster cheek pouches?
Cilnidipine, an L+N type calcium channel blocker, dilates both arterioles and venules, unlike nifedipine which only dilates arterioles, due to its additional action on N-type channels.
May support venodilation with cilnidipine in microcirculation models; leaves open clinical relevance versus L-type blockers.
Dihydropyridine calcium channel blockers are not uniform in terms of their action on calcium channel. L-type calcium channel blockers dilate the resistance arterioles. Cilnidipine is a dihydropyridine calcium channel blocker that also acts on N-type calcium channels, and may dilate venules through its effect on the sympathetic receptor. The influence of an L-type calcium channel blocker (nifedipine) or this L+N type blocker at 10(-7) mol to 10(-4) mol on venular diameter was examined by superfusion of male Syrian hamster cheek pouches. Nifedipine dose dependently dilated the arterioles alone, whereas cilnidipine dilated both arterioles and venules. Application of 10(-7) mol omega conotoxin, an inhibitor of N-type channels, after nifedipine led to significant dilation of venules, while it had no influence when administered after cilnidipine. These findings indicate that the effects of calcium channel blockers on the venules differ according to the action on N-type calcium channels, and that cilnidipine (an L+N type calcium channel blocker) dilates venules through its additional action on N-type channels.
No takes yet. Share an insight, caveat, or question.
Kushiro et al. (2004) studied this question. Cilnidipine vs. Nifedipine was evaluated on Venular diameter. Cilnidipine dilated both arterioles and venules in hamster cheek pouches, whereas nifedipine dilated arterioles alone, demonstrating the role of N-type calcium channels in venular dilation.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: