Changes in striatal somatostatin receptors in pups after cocaine administration to pregnant and nursing dams.

Primiparous female Wistar rats were injected subcutaneously with single daily doses of 40 mg of cocaine hydrochloride/kg from day 7 to 19 of gestation, from day 7 of gestation to day 15 postpartum or from parturation to day 15 postpartum. At birth, some of the offspring were fostered to control mothers to limit the effect of cocaine to the prenatal period and some were left with their mothers with the aim of studying prenatal plus postnatal exposure to cocaine. Prenatal and/or postnatal cocaine exposure did not affect the content of somatostatin (SS)-like immunoreactivity (SLI) in the striatum of the offspring as compared with the control groups on day 15 in all experimental groups. Prenatal and prenatal-plus-postnatal exposure to cocaine increased the total number of binding sites for 125I-Tyr11-SS in the rat striatum at 15 days of age. Prenatal exposure to cocaine also decreased the apparent affinity of the receptors. Postnatal exposure to cocaine alone had no such post-treatment effect on 125I-Tyr11-SS binding. These results suggest that the development of SS receptors in the rat striatum can be altered by prenatal exposure to cocaine.