EFFECT OF ACUTE STRESS ON PLASMA-CONCENTRATIONS OF SEX AND STRESS HORMONES IN JUVENILE ALLIGATORS LIVING IN CONTROL AND CONTAMINATED LAKES

Environmental contaminants can act as stressors, inducing elevated cir culating concentrations of stress hormones such as corticosterone and cortisol. Development in contaminated eggs has been reported to modify circulating sex steroid hormone concentrations in alligators (Alligat or mississippiensis). We examined plasma concentrations of testosteron e (T), estradiol-17 beta (E-2), and corticosterone (B) immediately upo n and two hours after capture in male and female juvenile alligators l iving in either contaminated or relatively pristine lake systems. We o bserved that plasma T concentration was significantly depressed in mal es from the contaminated lake, whereas plasma E, showed significant va riation between sexes but not between lakes. Initial plasma B concentr ations were similar between alligators from both lakes or either sex. Two hours of capture and restraint did not effect plasma T or E-2 conc entrations but was associated with a dramatic rise in plasma B concent rations. These data suggest that juvenile alligators exposed to contam inants in ovo are apparently unaffected in their rapid glucocorticoid response to acute stress.