Thermoregulatory effects of resiniferatoxin in the mouse: comparison with capsaicin.
Resiniferatoxin, an extremely irritant diterpene present in several members of the genus Euphorbia, produced an 8 C decrease in the rectal temperature of mice with an effective dose in the range of 2-20 micrograms/kg. The structurally related natural product capsaicin produced a similar magnitude of fall in body temperature, albeit with 1000-fold lower potency. Tolerance to the hypothermic effects of both compounds readily developed and cross-tolerance between the compounds was observed. The extreme potency of resiniferatoxin should facilitate biochemical analysis of the mechanism of action of this class of compounds.
de Vries
D J
DJ
Laboratory of Cellular Carcinogenesis and Tumor Promotion, National Cancer Institute, Bethesda, MD 20892.
Blumberg
P M
PM
D000818:Animals; D001831:Body Temperature / Q000187:drug effects*; D002211:Capsaicin / Q000008:administration & dosage / Q000494:pharmacology*; D004224:Diterpenes / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004361:Drug Tolerance; D005260:Female; D051379:Mice
D004224:Diterpenes; C024353:resiniferatoxin; D002211:Capsaicin