[Study on the functions of synthesis and release of gonadotropins of the pituitary gland in human subjects by LH-RH 2-step test].

The pituitary gonadotropin response of synthesis and release to two step stimulation by 100 micrograms of LH-RH at 60 minutes interval was studied by radioimmunoassay of LH and FSH in normal menstrual cycling and menopause women and adult males. The blood samples were collected before LH-RH stimulation and 30, 60, 90, 120 minute after the first stimulation, respectively. The value of delta 1 was defined as either higher value at 30 or 60 minute minus the value at 0 minute. The value of delta 2 was defined as either higher value at 90, 120, or 180 minute minus the value of 60 minute. delta 1 Was explained as the release of pituitary gonadotropin and delta 2 standed for the release and synthesis of pituitary gonadotropin. delta 1 delta 2 Ratio was expressed as delta 2/delta 1 100%. If delta 2 was higher than delta 1, subsequently the value of delta 1 delta 2 ratio was larger than 100. When delta 1 was more than delta 2, then the value of delta 1 delta 2 ratio was smaller than 100. In normal menstrual women delta 1 of LH were as Preovulatory phase greater than Follicular phase greater than or equal to Luteal phase, delta 2 were as Preovulatory phase greater than Luteal phase greater than Follicular phase. The value of both delta 1 and delta 2 of FSH were Preovulatory phase greater than Follicular phase greater than Luteal phase. The delta 1 of serum LH of menopause women and adult males were higher whereas delta 2 of both serum LH and FSH of adult males were extremely low in value. delta 1 And delta 2 of serum FSH in menopause women showed higher values than those of others. delta 1 delta 2 Ratio of LH and FSH of both follicular phase and luteal phase were more than 100, indicating dominant pattern of synthesis of gonadotropin. The delta 1 delta 2 ratio of LH at preovulatory phase and of both LH and FSH in menopause women and adult males were smaller than 100, suggesting dominant pattern of release of pituitary gonadotropin. These dates suggest that our LH-RH two step test was more useful to clarify anterior pituitary function in terms of both synthesis and release of gonadotropin.