Capsaicin (1 nM-1 mu M) induced a concentration-dependent decrease in heart
rate, coronary flow, aortic flow, left ventricular developed pressure and
its first derivative, dP/dt(max) in isolated working rat heart. The effect
of 10 nM capsaicin was mimicked by 0.1 nM endothelin. PD142893 (200 nM), a
non-selective endothelin receptor blocking agent antagonized the effect of
either endothelin (0.1 nM) or capsaicin (10 nM). We conclude that the major
ity of the effects of capsaicin in the rat heart are mediated by neural end
othelin release. (C) 1999 Elsevier Science B.V. All rights reserved.