PRENATAL ALCOHOL EXPOSURE RESULTS IN HYPERACTIVITY OF THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS OF THE OFFSPRING - MODULATION BY FOSTERING ATBIRTH AND POSTNATAL HANDLING

Exposure of fetal rats to alcohol results in permanent hyperactivity o f the hypothalamic-pituitary-adrenal (HPA) axis, In contrast, postnata l handling or fostering have been reported to restrain HPA activity. B ecause of the deleterious consequences of a hyperresponsive HPA axis, we thought that the possibility that postnatal manipulations might be able to reverse the influence of prenatal alcohol treatment deserved i nvestigation, To test this hypothesis, we exposed rat dams to alcohol by inhalation during the second week of gestation. At birth, pups were either fostered or remained with their dam, For the first 3 weeks, li tters were handled daily for 15 min or left undisturbed, At 22 days of age, male and female pups were decapitated under basal conditions, af ter 10 min of mild electro-footshock, or 10 min after footshock had be en terminated, As expected, prenatal exposure to alcohol induced incre ased adrenocorticotropin (ACTH) secretion in response to footshock, an d postnatal handling of control pups resulted in a suppression of cort icosterone and ACTH release, although changes in this latter hormone d id not reach statistical significance, Surprisingly, however, pups exp osed to alcohol that were also fostered and handled after birth, showe d an ACTH response to footshock stress that was significantly larger t han all other groups. This unexpected response may be due to alteratio ns in maternal-pup behaviors and may indicate that these manipulations act on different neuronal substrates within the central HPA of young rats, Further studies are needed to determine whether adrenal regulati on is also altered in animals exposed to alcohol prenatally and reared in a similar manner.