Effects of short- and long-term withdrawal from gestational cocaine treatment on maternal behavior and aggression in Sprague-Dawley rats.

Pregnant rats were treated with 30 mg/kg per day cocaine or normal saline either throughout gestation (GD 1-20, cocaine and saline withdrawal) or throughout the gestation and continuing into lactation for 10 days postpartum (cocaine and saline nonwithdrawal). All cocaine-treated dams exhibited more disruptions in the onset of maternal behavior (retrieval, licking, crouching) and were more aggressive (threats and attacks) towards an intruder on postpartum day 6 than saline-treated dams. There were no significant differences in these behaviors between withdrawn and nonwithdrawn cocaine-treated dams. These findings indicate that changes in maternal behavior following chronic moderate cocaine treatment are not simply the result of withdrawal from cocaine treatment following gestation and that other possible mechanisms should be examined.

Prenatal exposure to cocaine: effects on aggression in Sprague-Dawley rats.

Social/aggressive behavior in adult rat offspring (beginning at postnatal Day 180) prenatally exposed to saline, cocaine, or amfonelic acid (AFA) was examined. Pregnant rats received injections of 15 mg/kg of cocaine, or 0.9% saline twice daily, s.c., or on 2 consecutive days at 4-day intervals, or 1.5 mg/kg amfonelic acid daily throughout gestational Days 1-20. Frequency, duration, and latency of 11 social/aggressive behaviors were recorded for two 15-min sessions during which a smaller male intruder replaced an ovariectomized female in the resident's home cage. Subjects received a s.c. saline injection before Session 1 and 2.0 mg/kg of gepirone, a 5HT1a partial agonist, prior to Session 2. Prenatal cocaine treatment resulted in alterations of aggressive behavior. Aggressive behavior was reduced by gepirone in all groups but to a lesser extent in the AFA group.

Effects of chronic and acute cocaine treatment on the onset of maternal behavior and aggression in Sprague-Dawley rats.

Pregnant rats were treated either throughout gestation (GD 1-20) with 30 mg/kg per day (chronic cocaine) or with one 15-mg/kg dose immediately following parturition (acute cocaine). Chronic and acute cocaine treatment delayed or diminished the postpartum onset of some components of maternal behavior, and chronically treated dams were significantly more aggressive toward a male intruder than acute cocaine-treated or saline-treated dams. Cocaine increased the latency to crouch over pups and decreased crouch duration during a 30-min observation period that immediately followed parturition. Latencies to nest build were also longer in more chronic cocaine-treated dams than in saline controls. On Day 6 postpartum, 83% of chronic cocaine-treated dams pinned and attacked an intruder male 8 or more times during a 10-min observation period, whereas only 4% of acute cocaine-treated and none of the saline-treated dams exhibited this much aggression.

The effects of chronic prenatal exposure to nicotine on the behavior of guinea pigs (Cavia porcellus).

Three groups of 15 offspring from guinea pig dams were injected twice daily throughout gestation with one of three doses (0.5, 1.5 or 2.5 mg/kg) of nicotine-hydrogen tartrate. These offspring and 15 saline-exposed offspring were tested on several behavioral measures. Offspring of nicotine-treated dams had significantly lower rates of spontaneous alternation as neonates. The 1.5 and 2.5 mg/kg nicotine-exposed offspring also alternated less at puberty than control offspring and would not enter an unfamiliar stimulus alley that a majority of controls entered. Nicotine offspring, as adults, performed significantly poorer than their controls on errors and trials to criterion on a discrimination and reversal task. Prenatal nicotine treatment resulted in performance deficits on both learned and innate behavioral measures throughout development and adulthood.