Delayed anti-arrhythmic effect of nitroglycerin in anesthetized rats: involvement of CGRP, PKC and mK ATP channels.

Delayed anti-infarct and anti-stunning effects of nitroglycerin (NTG) have well been established in some animal models. The main goals of this study in anesthetized rats were to determine whether NTG has a delayed anti-arrhythmic effect and if so, whether calcitonin gene-related peptide (CGRP), protein kinase C (PKC) and mitochondrial K(ATP) channels (mK(ATP)) are involved in triggering this response. For this purpose, on day 0, male Wistar rats received NTG (120 microg/kg, iv) with or without pre-administration of PKC inhibitor chelerythrine (CHE), capsaicin (CAP) to deplete CGRP from sensory nerves or mK(ATP) channel blocker 5-hydroxydecaonic acid (5HD).