SUPPRESSION OF PEPTIDE YY-INDUCED HYPERPHAGIA BY TERBUTALINE

Central administrations of neuropeptide Y and peptide YY (PYY) produce robust increases in food intake, and this response may be contingent upon the availability of insulin. In contrast, beta2-adrenergic agonists decrease food intake, and this effect also appears to be dependent on circulating insulin. To investigate a possible interaction between PYY and beta2-adrenergic function, rats were given systemic injections of terbutaline, a beta2 agonist, at doses of 0, 5, 10, and 50 mg/kg prior to injections of 0.57 nmol PYY in the paraventricular nucleus of the hypothalamus. Terbutaline pretreatment significantly decreased feeding elicited by PYY in a dose-dependent fashion. This suggests that beta2-adrenoreceptor activity is involved in PYY-induced feeding.