A DOSE-RESPONSE STUDY OF CHRONIC COCAINE ON MATERNAL-BEHAVIOR IN RATS

To determine if there was a dose-response relationship with regard to cocaine treatment and maternal behavior exhibited by lactating rats at doses that had not been previously investigated, we examined the effe cts of three doses of chronic cocaine administration throughout gestat ion on both onset and established maternal behavior. Dams were injecte d (SC) with 6.3, 13, or 25 mg/kg cocaine HCl or an equivalent Volume o f saline throughout gestation; maternal behavior was tested on postpar tum days 1 and 3. At the doses employed, cocaine disrupted the onset o f only one pup-directed component of maternal behavior significantly i n a dose-response manner, although there were several statistically no nsignificant dose-dependent trends of behavioral disruptions. No pup-d irected behaviors were disrupted during testing for established matern al behavior. These results indicate that gestational cocaine treatment at doses of 25 mg/kg and less have only minimal effects on the onset and no effect on the maintenance of maternal behavior using our paradi gm. The relationship of the present findings to previous work is discu ssed. (C) 1998 Elsevier Science Inc.