[Neurobiological impact of separating mothers from newborns in rodents]

Numerous animal models of early stress are currently being developed because early stress results in long-term disruptions of neuronal functions and the development of long-term behavioral disorders. These models should allow to study the concept of vulnerability applied to psychiatric disorders. The fundamental importance of the bond between the mother and the offsprings, in all mammalian species, for the development of the new-born, point to the great interest of animal models of mother/pups separation. Long periods of deprivation tend to result in anxiety, depressive-like behaviors and drug addiction in adult rats. Neurobiological studies have shown that several neuronal systems, in particular neuropeptidergic systems in the limbic structures of the brain, are disrupted, possibly due to the effects of early stress on neurodevelopment. Models evaluating the impact of early environmental factors should help to improve the prevention and prediction of psychiatric disorders and to develop new therapeutic strategies.