Growth, development and activity in rat offspring following maternal drug exposure

Abstract

Seventy-nine Sprague-Dawley derived primiparous rats were injected subcutaneously throughout pregnancy and the nursing period with either (1) 3.0 mg/kg of pure nicotine, (2) 5.0 mg/kg methamphetamine HCL, (3) saline vehicle, or, (4) non-injected. Vital and developmental measures were taken on the offspring throughout the nursing period and for one additional week. Methamphetamine-injected females had a shorter, and nicotine-injected females a longer gestational period, and both gained less weight over the 21-day period than the control groups. The pups of methamphetamine and nicotine dams were significantly underweight at birth and the 28 day postnatal period and exhibited developmental delay. Male offspring were divided into behavioral, aging, and autopsy groups on Day 28. Male offspring of methampetamine-injected dams remained significantly lighter in weight for the first 15 months of life (aging groups). Their counterparts in the behavioral groups and the offspring of non-injected dams exhibited significantly greater activity for eight of the first twelve monthly assessments which began at 90 days of age. Additional vital, performance, and sensory measures will continue throughout the lifespan of the animals.