Maternal regulation of the adrenocortical response in preweanling rats.
In the following studies, we investigated the effects of 24-h maternal deprivation on the infant's hypothalamic-pituitary-adrenal system. Experiment 1 examined the effect of deprivation on the infant's corticosterone (CORT) response to adrenocorticotropin hormone (ACTH) injection. At all ages studied, deprivation resulted in a potentiation of the response. At some ages, deprived nontreated pups had higher CORT levels than nondeprived pups. Experiment 2 examined the ontogeny of the deprivation-induced stress response, and the capacity of the mother to inhibit it. From 8 days of age onwards, deprived animals showed a CORT response to saline injection that was either absent or far smaller in nondeprived pups. Saline-induced CORT secretion was diminished, or prevented, by returning the infant to its dam. Maternal reunion had no effect on ACTH-induced CORT elevations. Finally, Experiment 3 investigated the effects of deprivation over a more extended period of time. In maternally deprived pups, ACTH-induced CORT elevations persisted for at least 2 h following reunion, but by 6 h had returned to baseline. These data suggest that maternal factors are involved in the regulation of the responsiveness of the pup's hypothalamic-pituitary-adrenal system.
Rosenfeld
P
P
Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine Stanford University, CA 94305.
Gutierrez
Y A
YA
Martin
A M
AM
Mallett
H A
HA
Alleva
E
E
Levine
S
S
D000302:Adrenal Cortex / Q000294:innervation*; D000324:Adrenocorticotropic Hormone / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn / Q000502:physiology; D001143:Arousal / Q000502:physiology*; D003345:Corticosterone / Q000097:blood*; D005260:Female; D007030:Hypothalamo-Hypophyseal System / Q000502:physiology*; D008297:Male; D008425:Maternal Behavior; D008426:Maternal Deprivation; D010913:Pituitary-Adrenal System / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains
D000324:Adrenocorticotropic Hormone; D003345:Corticosterone