DELAYED AROUSAL FROM ANESTHESIA - A FURTHER SIMILARITY BETWEEN STRESSAND BETA-1 ADRENOCEPTOR BLOCKADE

The present studies investigated the role of beta adrenergic receptors in mediating arousal from anesthesia and the effects of stress on thi s process. In support of previous findings by others, it was found tha t blockade of beta-1 and beta-2 receptors by propranolol delayed arous al from halothane anesthesia and that this effect was attributable to blockade of beta-1 receptors because it was duplicated by betaxolol bu t not by ICI 118,551. Restraint stress also produced a delay in arousa l from both halothane and hexobarbital anesthesia. This effect, which was observed at 0.5 but not 24 h after the stress, could not be explai ned by a stress-induced alteration in the metabolism of the anesthetic , as no difference in brain concentration of hexobarbital was found be tween stressed and control mice. The parallel effects of beta-1 blocka de and stress further supports the hypothesis that stress produces an impairment in function at either the beta-1 receptor or some process c oupled to this receptor.