ISSN:
1432-2013
Keywords:
Temperature regulation
;
Beta-endorphin
;
Hypothermia
;
Serotonin
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract The effects of intraventricular administration of beta-endorphin on thermoregulatory responses of unanesthetized rats to different ambient temperatures (T a ) of 8, 22 and 30°C were assessed. Administration of beta-endorphin produced a fall in rectal temperature at bothT a 8 and 22°C. The hypothermia in response to beta-endorphin was brought about by both cutaneous vasodilation (as indicated by an increase in both the tail and the foot skin temperatures) and decreases in metabolic heat production. However, atT a 30°C, administration of beta-endorphin produced no change in rectal temperature or other thermoregulatory responses. Furthermore, the hypothermic effect induced by beta-endorphin was greatly attenuated by either the depletion of brain serotonin levels (with 5,6-dihydroxytryptamine andp-chlorophenylanine) or the blockade of opiate receptors (with naloxone). The data indicate that beta-endorphin leads to hypothermia in rats by increasing sensible heat loss and decreasing metabolic heat production, probably via the release of endogenous serotonin within brain.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00585909
