Adolescent cocaine and injection stress effects on the estrous cycle

摘要: Chronic cocaine exposure during critical periods of development induces short- and long-term effects. During the pubertal period, hypothalamic-pituitary-gonadal (HPG) axis undergoes many dynamic changes. The present study investigated whether chronic periadolescent alters reproductive maturity in rat. Sixty female Long-Evans hooded rats were randomly assigned to one three conditions (20 mg cocaine/kg/day, saline injected uninjected), for dosing from postnatal day 21 (P21) through P60. Several indicators maturation functioning assessed following treatment. Cocaine had no effect on onset puberty or date first ovulation. number proestrus-estrus transitions was significantly lower cocaine-exposed females compared uninjected females, but not saline-injected controls. This reduction observed cocaine, as well after cessation injections. also exhibited a greater cycles that clear P-E transition than did UN subjects; this disappeared once injections stopped. These alterations suggest immediate, possibly persisting, control ovulation throughout adolescence. Interestingly, injection diestrus days cocaine-injected animals, proportion regular 4- 5-day cycles. differences results stress-induced irregularity estrous cycle, attenuated by recoverable exposure. findings indicate HPG is susceptible short-term, long-term, induced adolescent period.