Dose-dependent effects of multiple acute cocaine injections on maternal behavior and aggression in Sprague-Dawley rats

Rat dams, which had no prior drug treatment, were either nontreated control s or were injected subcutaneously 4 times during a 10-day period with a sin gle dose of 30, 15 or 7.5 mg/kg of cocaine hydrochloride HCl, or normal sal ine. Injections were given immediately postpartum following delivery of the ir final pup (PPD 1), and again on postpartum day 3 (PPD 3), postpartum day 6 (PPD 6) and postpartum day 10 (PPD 10). Dams were observed 30 min follow ing injections for maternal behavior (MB) towards 8 surrogate male pups on PPD 1 and PPD 3 and for aggression towards a male or female intruder in the presence of their litter on PPD 6 and PPD 10. Compared to saline and untre ated controls, cocaine-treated dams exhibited more disruptions in MB on bot h PPD 1 and PPD 3 and were less aggressive towards an intruder, regardless of intruder sex, on PPD 6 and PPD 10. In most cases MB was altered in a dos e-dependent manner with the higher doses of cocaine resulting in a greater disruption of behavior.