The concentrations of melatonin in 112 preovulatory follicular fluid (FF) samples obtained from 60 women undergoing in vitro fertilization and 27 patients at laparotomy during a spontaneous cycle were measured by RIA and compared with those in peripheral serum. The circadian and seasonal variations in FF melatonin were also analyzed. The FF melatonin concentrations in stimulated (mean +/- SEM, 61.9 +/- 6.4 pmol/L) and spontaneous cycles (98.1 +/- 8.9 pmol/L) were significantly higher (P less than 0.005) than those in peripheral serum (25.4 +/- 1.2 and 38.6 +/- 1.8 pmol/L, respectively), and in the stimulated cycles there was a positive correlation between them. The FF melatonin concentration in the morning (58.9 +/- 3.8 pmol/L) was significantly higher (P less than 0.005) than that in the daytime (23.2 +/- 0.8 pmol/L), but the morning concentrations did not differ between the light and the dark seasons of the year, whereas the daytime values were higher (P less than 0.005) during the dark season (27.1 +/- 2.1 pmol/L) than during the light season (21.1 +/- 2.1 pmol/L). The FF melatonin concentration did not correlate with follicular volume, and FF and serum melatonin concentrations showed no significant correlation with the serum concentrations of estradiol, progesterone, testosterone, or PRL. There were also no differences between FF melatonin concentrations in aspirates with or without an ovum. In summary, significant circadian and circannual variations in high FF melatonin concentrations were found, which suggest that melatonin could potentially interfere with the regulation of reproduction in humans at the follicular level.

In order to try to clarify the often supposed stimulating effect of clomiphene citrate on spermatogenesis a controlled double-blind cross-over trial was used. 30 pre-selected normogonadotropic infertile men were given 50 mg clomiphene citrate daily or placebo in a double-blind cross-over fashion for three months, each treatment period being separated by three to four months. On clomiphene treatment the median sperm count increased from 13.3 to 28.7 mill/ml (P < 0.001). During the placebo treatment schedules the median sperm count remained unchanged (P < 0.05). The increases of FSH, LH, testosterone, and oestradiol were highly significant (P < 0.001) during the clomiphene treatment but during placebo treatment the median hormone levels did not change (P < 0.05). Three pregnancies occurred due to clomiphene treatment and one occurred during placebo treatment.

No abstract

Serum bioactive and immunoreactive LH and FSH were measured in clinical conditions with increased or decreased gonadotropin secretion. Gonadotropin immunoreactivity was measured using a conventional RIA (I) and an ultrasensitive immunofluorometric method (F). Bioactive (B) LH was assessed by the mouse interstitial cells in vitro bioassay, and B-FSH using the immature rat granulosa cell assay. Acute GnRH stimulation of adult men (n = 6) increased LH levels measured by the different methods 4.3- to 5.3-fold. The B/I ratio of LH increased from 2.34 +/- 0.21 to 3.71 +/- 0.36 (mean +/- SEM) at 120 min (P less than 0.05), but no change was found in the B/F ratio. After ovariectomy of premenopausal women (n = 6), the LH levels increased in 1 week 4- to 6-fold, the B/I ratio from 1.85 +/- 0.22 to 2.59 +/- 0.24, and the B/F ratio from 1.78 +/- 0.22 to 2.90 +/- 0.30 (P less than 0.05 for both). In addition, the LH levels were measured during GnRH agonist treatment of ovarian carcinoma (n = 8), endometriosis (n = 8), and prostatic carcinoma after orchiectomy (n = 8). In the two former groups, serum B-LH decreased in 1 month to undetectable levels (less than 0.5 IU/L), and in the prostate cancer patients to 1.2 (0.8-1.9) IU/L (log mean and range of +/- SEM). The concomitant decline of I-LH was to 1.5-1.9 IU/L in the agonist-treated female patients, and that of F-LH to 0.10-0.15 IU/L; in the prostate cancer patients, respectively, these values were 7-8 and 0.3-0.7 IU/L. The B/I and B/F ratios during the agonist treatments could only be calculated in the prostate cancer patients (in the others, B-LH became undetectable). The B/I ratio decreased from 2.34 +/- 0.5 to 0.14 +/- 0.03 (P less than 0.01), but no suppression was found in the B/F ratio from a pretreatment value of 3.6 +/- 0.8. B-, I-, and F-FSH levels were measured in the GnRH agonist-treated orchiectomized prostate cancer patients. The pretreatment level of B-FSH was 154 (137-175), that of I-FSH was 38.0 (34.4-42.0), and that of F-FSH was 39.8 (35.3-44.9) IU/L. The B/I ratio of FSH was 3.76 +/- 0.49, and the B/F ratio was 3.53 +/- 0.59. The mean B-FSH level decreased during treatment by 87-93.5%, that of I-FSH by 98%, and that of F-FSH by 91.5% (P less than 0.01 for all).(ABSTRACT TRUNCATED AT 400 WORDS)

Clomiphene citrate was administered as a 50 mg oral daily dose to 44 normogonadotrophic (serum FSH 2-10 mIU/ml) subfertile men for 3 months. The treatment resulted in significant increases in FSH and LH concentrations, whereas prolactin remained unchanged. Serum testosterone and oestradiol both increased highly significantly. The increased testosterone levels suggest that the elevated LH levels had not led to "down regulation" of Leydig cell LH/hCG receptors, neither had the greatly increased estradiol led to depletion of these receptors. This is suggested to be a result of the blocking of testicular oestradiol receptors by the estrogen antagonist, clomiphene. Sperm count increased highly unchanged. The spermatic fluid concentrations of zinc and magnesium ions were also increased, whereas fructose remained unchanged. The katalytic activity of acid phosphatase in spermatic fluid increased highly significantly, whereas the concentration of the main prostate-specific acid phosphatase, as measured by a specific radioimmunological method, remained unchanged. Therefore, the increased Zn and Mg ion concentrations may be responsible for activation of acid phosphatase (s) in semen, or the treatment led to increased secretion of other prostatic acid phosphatase(s) than the main enzyme. However, it is clear that the secretion of the main prostatic acid phosphatase into semen is under different control than that of Zn++ and Mg++.