Effect of bombesin on core temperature in rats: studies involving radiotelemetry.

The effect of centrally administered bombesin on core temperature was investigated in rats which had been chronically fitted with a cannula in the third cerebral ventricle and with an intraperitoneal temperature-monitoring radiotransmitter. Intracerebroventricularly administered bombesin (0.01, 0.1 or 1 microgram) resulted in hypothermia, the duration and depth of the effect being a function of the dose. The use of telemetry minimized experimental interventions in this study; the results demonstrate that the hypothermic response to bombesin is not dependent upon exposure to a low ambient temperature, food restriction or insulin treatment as suggested by previous studies involving measurement of core temperature by a rectal probe.