EFFECTS OF BODY-WEIGHT ON RESPONSES OF SERUM PROLACTIN TO METOCLOPRAMIDE AND THYROTROPIN-RELEASING-HORMONE IN SECONDARY AMENORRHEIC WOMEN

The present study was designed to investigate the influence of body weight on the prolactin responsiveness to metoclopramide and thyrotrophin-releasing hormone (TRH) in secondary amenorrhoeic women. The responses of serum prolactin to metoclopramide and TRH were assessed in relation to body mass index (BMI). Doses of 10 mg of metoclopramide hydrochloride and 500 mu g of TRH were administered i.v. to 42 secondary amenorrhoeic women and six women with primary ovarian failure. The increment of serum prolactin at 30 min after the administration of metoclopramide was significantly lower (P < 0.01, respectively) in amenorrhoeic women with a BMI of greater than or equal to 30 or < 19 than in amenorrhoeic women with a BMI of 19-24. A significant correlation ratio (eta = 0.63; P < 0.01) was found between the BMI and the increment of serum prolactin at 30 min after metoclopramide administration in amenorrhoeic women. The increment of serum prolactin at 15 min after TRH administration was slightly lower in amenorrhoeic women with a BMI of greater than or equal to 30 or < 19 than in amenorrhoeic women with a BMI of 19-24, but these differences were not statistically significant. These results indicate that the body weight influences the responsiveness of serum prolactin to metoclopramide in secondary amenorrhoeic women.