Modification of prenatal stress effects in rats by adrenalectomy, dexamethasone and chlorpromazine.
This study was designed as a 4 (maternal treatments) by 2 (prenatal stress) factorial. The 4 treatment groups were: chlorpromazine (CPZ) 2.1 mg/kg; dexamethasone (DEX) 38.7 mug/kg; adrenalectomy (ADX); and controls (CON). Half of the females in each group were stressed prior to mating and during gestation. Stress significantly reduced birth and weaning weights of CON offspring but did not affect the weight of CPZ, DEX or ADX offspring. At birth, DEX and ADX offsrping, as well as offspring of partially adrenalectomized females, were significantly lighter than controls; at weaning, only the DEX animals displayed a weight deficit. Stress increased open field activity of ADX offspring but decreased the activity of DEX offspring while the performance of CON and CPZ offspring was not affected. In a food deprivation test at 42 days there were significantly more deaths among male offspring of no stress (32 percent) than of stress (4 percent) females and stress offspring in all groups lost less weight than unstressed offspring in a food deprivation test at 69 days. Avoidance conditioning tests showed effects only in female offspring. Stress significantly decreased avoidances made by CON offspring and increased avoidances made by DEX offspring. Treatment with ADX, CPZ or DEX can prevent the effects of prenatal stress on some characteristics of the offspring, but in other cases the effects are potentiated by these manipulations.
D000315:Adrenalectomy; D000818:Animals; D000831:Animals, Newborn / Q000254:growth & development*; D001362:Avoidance Learning; D001835:Body Weight; D002746:Chlorpromazine / Q000494:pharmacology*; D003907:Dexamethasone / Q000494:pharmacology*; D005106:Exploratory Behavior; D005260:Female; D005508:Food Deprivation; D008297:Male; D009043:Motor Activity; D011247:Pregnancy; D051381:Rats; D013312:Stress, Physiological
D003907:Dexamethasone; D002746:Chlorpromazine