Effects of 6-hydroxydopamine and amphetamine on rat mothering behavior and offspring development.

Selective CNS dopamine depletion was produced in neonatal female rats by administration of 6-hydroxydopamine and desmethylimipramine. These rats were subsequently tested as adults for maternal behavior toward their own offspring and received d-amphetamine prior to half of these sessions. The effects of early, selective CNS dopamine depletion and its related developmental disruptions on later care of offspring and response to amphetamine were thereby assessed. Pup retrieval, nest building, crouching, and locomotor behaviors were studied in 6-OHDA + DMI treated mothers while offspring were examined with respect to weight, density of fur, age of eye opening, and shuttlebox avoidance learning. Depletion of brain dopamine to 30% of control concentrations was associated with increased crouching time but with no other differences in caregiving, offspring development, or response to amphetamine. Although profound neonatal depletion of dopamine leads to a variety of disturbances in early life, later maternal behavior is adequate and apparently enhanced. The possible role of compensatory brain mechanisms is discussed.