Prenatal alcohol exposure and pineal response to isoproterenol, vasoactive intestinal polypeptide, and desmethylimipramine.

Pineals from neonatal rats born to alcohol-fed mothers had lower unstimulated serotonin-N-acetyltransferase activity (NAT) and responded less to isoproterenol, vasoactive intestinal polypeptide, or desmethylimipramine challenge than did pineals from pups born to normal or pair-fed mothers. Group differences disappeared after the first week of life. Reduced NAT activity is coincident with elevated glucocorticoids in these pups. In contrast to these effects of chronic in utero ethanol exposure, acute ethanol addition to normal adult pineals in organ culture enhanced ISO but not VIP stimulation of NAT activity. The results suggest that the neonatal pineal is more affected by ethanol-induced activation of the adrenocortical axis during gestation than by the direct effect of ethanol on membrane fluidity.