Estradiol enhances conditioned place preference to cocaine in male rats

Abstract

Gender differences are reported in the subjective effects of cocaine, as well as in the response to treatment. Animal studies show that in ovariectomized rats, estradiol enhances sensitization, as well as conditioned place preference to cocaine. Furthermore, blocking estrogen receptors with ICI 182,780, in gonadally intact females blocks cocaine‐induced behavioral sensitization and conditioned place preference. We observed a similar situation in males. Gonadectomized males that receive estradiol, but not DHT, become sensitized to cocaine after repeated administration. Administration of ICI 182,780 curtails the development of conditioned place preference to repeated cocaine injections in gonadally intact males. These results indicate that estrogen receptors are essential for conditioning to the rewarding effects of cocaine. We are currently exploring the mechanism involved. This work was supported by the NINDS Specialized Neuroscience Research Program of the U54NS39405 and the NIGMS RISE Program R25Gm061838.