ARE SOME OF THE EFFECTS OF ETHANOL-MEDIATED THROUGH NPY

Central administration of neuropeptide Y (NPY) in low concentrations h as been shown to produce anxiolysis and suppression of locomotor activ ity, a behavioral profile not dissimilar to that of ethanol. The prese nt study was conducted to ascertain whether NPY and ethanol have simil ar electrophysiological profiles and to evaluate the combined actions of NPY and ethanol. Eighty-five Wistar rats were stereotaxically impla nted with electrodes aimed at dorsal hippocampus, amygdala, and fronta l cortex. Rats were administered NPY [or saline (SAL)] intracerebroven tricularly (ICV) whereas the doses of alcohol (or SAL) were given intr aperitoneally (IP). Two doses of alcohol (0.75, 1.5 g/kg) and two dose s of NPY (1, 3 nmol) were given alone and in combination. Drug effects were assessed using event related potentials (ERP) recorded in respon se to an auditory ''odd-ball'' plus noise paradigm between 30 and 40 m in postdrug. Multivariate analyses of variance (MANOVA) revealed that: NPY produced a significant decrease in the amplitude and increase in the latency of the N1 component in cortex and a decrease in the amplit ude of the P3 component in amygdala, but no overall effects in hippoca mpus. Ethanol produced identical effects to NPY on the N1 and P3 compo nents of the ERP in cortex and amygdala. Combined administration of Et OH and NPY (1 nmol) produced effects equivalent to those seen followin g the higher doses of NPY (3 nmol) or EtOH (1.5 g/kg). These studies d emonstrate that NPY and ethanol have a similar electrophysiological pr ofile. In addition, the combined administration of NPY and ethanol pro duced additive effects.