Effect of dermorphin on thermoregulation in rats at selected ambient temperatures

• Published in: Peptides (New York, N.Y. : 1980) Vol. 17; no. 2; pp. 241 - 245
• Main Authors: Emel'Yanova, T.G., Usenko, A.B., Deigin, V.I., Yarova, E.P., Kamensky, A.A.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 1996
• Subjects: Analgesics, Opioid - pharmacology; Animals; Body Temperature Regulation - drug effects; Dermorphin; Dose-Response Relationship, Drug; Environment, Controlled; Hyperthermia; Hypothermia; Male; Naloxone; Naloxone - administration & dosage; Naloxone - pharmacology; Oligopeptides - administration & dosage; Oligopeptides - pharmacology; Opioid Peptides; Rats; Skin Temperature - drug effects; Thermoregulation; Vasoconstriction; Vasodilatation; Naloxone; Vasoconstriction; Thermoregulation; Vasodilatation; Hyperthermia; Dermorphin; Hypothermia
• ISSN: 0196-9781; 1873-5169
• DOI: 10.1016/0196-9781(95)02132-9

Intraperitoneal administration of dermorphin caused dose-dependent changes in rats core temperature and tail skin temperature (indicative of compensatory thermoregulatory vasoreactions in rats). The character of these changes depended strongly on the environmental temperature at which the inversion of the dermorphin-induced thermoregulatory effect was observed. In the cold environment (4–7°C) dermorphin caused a significant, stable, dose-dependent hypothermia. In the thermoneutral environment (27–28°C) dermorphin also caused hypothermia, but this effect was less pronounced. In the hot environment (31–32°C) dermorphin caused hyperthermia. Dermorphin-induced changes in tail skin temperature indicate that dermorphin suppresses the thermoregulatory peripheral compensatory vasomotor reactions. Pretreatment with naloxone attenuated dermorphin-induced effects on core temperature and partially enhanced vasomotor effects of dermorphin. The data obtained indicate that dermorphin affects the core temperature regulation via μ-opiate receptors, whereas vasomotor effects of the peptide are probably mediated via naloxone-insensitive receptors.