Figure 1.

Early-life stress evokes transitory alterations of neuroendocrine parameters. A, Representative analysis grids of maternal behavior. Left, A dam rearing pups in a normal cage environment; right, a dam rearing pups in a cage with reduced nesting material. Grids depict 25 consecutive 3 min epochs and types of “nurturing” behaviors are color coded as follows: blue, nursing; yellow, carrying pups; green, licking/grooming; red, off pups; and pink, self grooming. B, Dams limited in nesting material spend less time nursing and more time off their pups. C, Parameters indicative of stress immediately after the early-life stress period (P9; left column) and in middle-aged rats (12 months of age; right column). Elevated basal corticosterone levels, higher adrenal gland weights, and modestly lower body weight were found in chronically stressed P9 rats (n = 12 per group), but these changes were no longer present in middle-aged rats (n = 5 controls, 6 early stress). All studies and plasma harvest (by decapitation) were performed from 8:00 A.M. to 10:00 A.M. (^*p < 0.05; Student's t test). Error bars represent SEM.