The behavioral response to novelty is altered in rats neonatally exposed to cocaine

✍ Scribed by Jennifer A. Willford; Tracy M. Segar; Susan Barron

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 166 KB
• Volume: 35
• Category: Article
• ISSN: 0012-1630
• DOI: 10.1002/(sici)1098-2302(199912)35:4<343::aid-dev8>3.0.co;2-e

✦ Synopsis

It has recently been suggested that the effects of in utero cocaine exposure may result in subtle deficits related to a challenging environment, including exposure to novelty or stress. This study used a neonatal drug-exposure model to examine the behavioral response to a novel environment in rodents. Subjects were artificially reared (AR) from postnatal Days 4-10. There were four treatment groups; AR 40 mg/kg/day cocaine, AR 20 mg/kg/day cocaine, AR control group receiving no drug, and a normally reared control. In Experiment 1, subjects were tested for their preference of maternal home-cage or clean wood-chip odors in a T-maze on postnatal Day 15. Subjects from all treatment groups preferred the maternal odor. In Experiment 2, subjects were habituated to four familiar odors and tested with a novel odor in an open field . Neonatal exposure to 20 mg/kg/day cocaine led to an overall increase in exploratory behavior during testing, whereas 40 mg/kg/day did not, supporting the hypothesis that developmental exposure to cocaine at some doses may alter the offspring's response to a changing environment.