Hormonal mediation of the analgesia produced by food deprivation.

Research has demonstrated that a wide variety of environmental conditions are capable of producing analgesia. In the present experiment, the analgesia produced by 24 hr of food deprivation was examined following adrenalectomy, hypophysectomy, naltrexone (7 mg/kg), dexamethasone (0.4 mg/kg), or saline treatment. Results revealed that 24 hr of starvation elicited an analgesic response in the saline-treated and sham-operated groups. Naltrexone, dexamethasone, adrenalectomy, and hypophysectomy blocked the analgesia produced by food deprivation. The results demonstrate that 24 hr of food deprivation induced an opiate-mediated analgesic system that involves hormonal factors.