Interplay between nitric oxide and CGRP by capsaicin in isolated guinea-pig heart.
Capsaicin at a concentration of 10(-7)m induced a significant increase in heart rate and increased coronary flow in isolated Langendorff-perfused guinea-pig hearts. This effect was completely blocked by 30 microm of N(omega)-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide synthase. Additional incubation with 3 m m L-Arg antagonized the inhibitory effect of L-NAME. In the presence of 1 microm of a human calcitonin gene-related peptide fragment (hCGRP 8-37), a CGRP-receptor antagonist, L-Arg was without effect. We conclude that a capsaicin-induced increase in coronary flow and heart rate is dependent from an interplay between CGRP and NO in guinea-pig hearts. 1999 Academic Press.
Oroszi
G
G
Department of Pharmacology and Pharmacotherapy, Medical University of Pecs and Neuropharmacology Research Group of the Hungarian Academy of Sciences, Pecs, H-7643, Hungary.
Szilvassy
Z
Z
Nemeth
J
J
Tosaki
A
A
Szolcsanyi
J
J
D000818:Animals; D001120:Arginine / Q000494:pharmacology; D015740:Calcitonin Gene-Related Peptide / Q000494:pharmacology*; D000077221:Calcitonin Gene-Related Peptide Receptor Antagonists; D002211:Capsaicin / Q000494:pharmacology*; D003326:Coronary Circulation / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006168:Guinea Pigs; D006321:Heart / Q000187:drug effects* / Q000502:physiology; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D017942:Nitric Acid / Q000378:metabolism*
D000077221:Calcitonin Gene-Related Peptide Receptor Antagonists; D004791:Enzyme Inhibitors; D017942:Nitric Acid; D001120:Arginine; D015740:Calcitonin Gene-Related Peptide; D002211:Capsaicin; D019331:NG-Nitroarginine Methyl Ester