GESTATIONAL EXPOSURE TO COCAINE OR PHARMACOLOGICALLY RELATED-COMPOUNDS - EFFECTS ON BEHAVIOR AND STRIATAL DOPAMINE-RECEPTORS

Gestational cocaine (COC) exposure has been reported to alter behavior and possibly dopamine (DA) receptors. In this paper, we further exami ned the effects of prenatal COC (40 mg/kg, s.c.) on DA receptor bindin g and the behavioral response to quinpirole, a DA D-2 receptor agonist . In an attempt to elucidate possible mechanisms of such effects, we e xposed pregnant dams to specific reuptake blockers; fluoxetine 12.5 mg /kg, a serotonin reuptake blocker; desipramine 10 mg/kg, a norepinephr ine reuptake blocker; GBR-12909 10 mg/kg, a DA reuptake blocker; or to a local anesthetic, lidocaine 40 mg/kg. Drugs were administered once daily over gestational days 8-20. Control dams were injected with sali ne (SAL) or pair-fed to the COC group. Quinpirole challenge was perfor med in the offspring on post natal day 19. Two pups per litter were in jected (s.c.) with 0.03 or 0.09 mg/kg quinpirole-HCl on post-natal day 19. The remaining pups in each litter were sacrificed for analysis of -striatal DA receptors. Results showed that only COC exposure altered the behavioral response to the quinpirole challenge by increasing quin pirole-induced stereotypy and motor activity relative to SAL controls. DA receptor analysis showed no alteration in K-D or B-MAX for striata l D-1 or D-2 sites in any group. These results suggest that prenatal C OC exposure produces alterations in function of the D-2 receptor compl ex which are not reflected in K-D or B-MAX and that these effects are not fully mimicked by exposure to specific monoamine reuptake blockers or a local anesthetic.