Postpartum exposure to triethyl tin produces long-term alterations in responsiveness to apomorphine.

Male and female rat pups were exposed to a single dose of triethyl tin (TET) or ethanol vehicle on day 5 postnatally and tested for responsiveness to apomorphine as adults. TET-exposed animals displayed an increased response to the stereotypic effects of 1 mg/kg of apomorphine. Female rats exposed neonatally to TET had decreased baseline rates of responding on a food reinforced variable interval (VI) 15 sec. schedule, while TET-exposed males were found to have increased baseline rates relative to controls. The rats maintained on a VI 15 sec. schedule were given various doses of apomorphine (0.0312-0.25 mg/kg, s.c.). Neonatal exposure to TET had no effect on the disruptive effects of apomorphine on VI 15 sec. responding. These data show an altered responsiveness of TET-exposed animals to higher doses of apomorphine (1 mg/kg), but not to lower doses of apomorphine (0.0312-0.25 mg/kg). The present data are in accord with the hypothesis that one of the long-term consequences of neonatal exposure to TET might be an alteration in the responsiveness of the dopamine system.