THE EFFECTS OF AGE, GENDER, AND SEASON ON SEROTONERGIC FUNCTION IN HEALTHY-SUBJECTS

1. Several factors, including age, gender, and season of the year, hav e been reported to affect physiologic indices of central serotonergic function, although some of these findings have not been consistent acr oss groups of subjects and types of serotonergic measures. 2. The auth ors investigated the role that each of these variables might play in t he neuroendocrine response to acute intravenous challenge with the ser otonin reuptake inhibitor clomipramine (CMI) in healthy volunteers. 3. Thirty seven healthy subjects (17 women and 20 men), with an age rang e of 19 to 50 years, received 12.5 mg of CMI intravenously under stand ardized conditions. 4. The maximum change from baseline in plasma prol actin concentrations (''delta-max'') was significantly related to age, after controlling for gender and season. 5. In contrast, neither gend er nor season was significantly related to prolactin delta-max, after controlling for the other two variables. 6. Although the age range and sample size are relatively limited, the results from this study sugge st that age, but not gender or season, may influence serotonergic func tion, as measured by the prolactin response to CMI challenge.