1. ¹Faculty of Life Sciences and The Leslie and Susan Gonda (Goldschmied) Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel
2. ²Biological Psychiatry, Felsenstein Medical Research Center, Beilinson Campus, Petah-Tikva, Israel
3. ³Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel

Correspondence: Dr G Yadid, Department of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel. Tel: +972 3 531 8123; Fax: +972 3 535 1824; E-mail: yadidg@mail.biu.ac.il

Received 10 August 2005; Revised 8 November 2005; Accepted 9 November 2005; Published online 18 January 2006.

Abstract

Dehydroepiandrosterone (DHEA), which can act as a potential antidepressant in both animals and humans, appears to lower distress involved with cocaine withdrawal. In fact, a role for neurosteroids in modulation of substance-seeking behavior is becoming increasingly clear. Therefore, we tested the effects of DHEA on the self-administration of cocaine (1 mg/kg/infusion) by rats. At maintenance, a relatively low dose of exogenous DHEA (2 mg/kg; i.p.) attenuated cocaine self-administration after several days of chronic treatment. More than 2 weeks (19 days) of daily DHEA injections were required to decrease the cocaine-seeking behavior of rats to less than 20% of their maintenance levels. DHEA does not seem to decrease cocaine self-administration by increasing the reinforcing properties of the drug, as indicated by a cocaine dose–response determination. After being subjected to extinction conditions in the presence of DHEA, rats demonstrated a minimal response to acute exposure to cocaine (10 mg/kg), which indicated a protective effect of DHEA on relapse to cocaine usage. Our results suggest a potential role for the neurosteroid DHEA in controlling cocaine-seeking behavior, by reducing both the desire for cocaine usage and the incidence of relapse.