CHRONIC COCAINE EXPOSURE AFFECTS STIMULUS-INDUCED BUT NOT SPONTANEOUSBEHAVIOR OF THE NEAR-TERM MOUSE FETUS

Pregnant female mice were injected subcutaneously with a 40-mg/kg dose of cocaine-HCl or physiological saline from day 1 through day 17 of g estation. On day 18 of gestation, darns were surgically prepared to al low the behavior of their fetuses to be observed. Spontaneous motor be havior was unaffected by cocaine exposure. Cocaine exposure potentiate d motor responses of the fetuses to ammonia and to control injections of saline into the amniotic sac. Restriction of umbilical blood now ca used a specific stereotyped response in saline-injected fetuses, which is in agreement with studies of other species. This response was mark edly potentiated in fetuses exposed to cocaine. The results suggest th at the mouse may be a viable model for studies of the neurodevelopment al effects of gestational cocaine exposure and are discussed in relati on to current models of the effects of long-term cocaine exposure on b rain neurochemistry. (C) 1997 Elsevier Science Inc.