Elicitation and modification of the acoustic startle reflex in animals prenatally exposed to cocaine.

In separate experiments, pregnant Long-Evans rats were administered cocaine orally (60 mg/kg/day) on gestation days 14-21, or subcutaneously (40 mg/kg/day) on gestational days 8-21. For each route of administration, a vehicle control group was pair-fed to the group administered cocaine and another control group was left untreated. Throughout pregnancy, the dams that received cocaine gained approximately 15% less weight than the untreated controls, but none of the dosage procedures affected the size of the litters, or the weight and growth of the offspring. When the offspring reached adulthood, various assessments of reflex function were made using the acoustic startle reflex and prepulse inhibition of startle. There were no effects on startle habituation or reflex modification that could be attributed to the prenatal exposure to cocaine.