Elevated Serum FSH Levels Research Articles

Long-Term Effects of Endocrine Treatment on Serum Pituitary Hormones in Advanced Prostatic Carcinoma Patients

Peripheral serum concentrations of FSH, LH, prolactin and ACTH were measured in 22 patients with advanced prostatic carcinoma treated by castration, polyestradiol phosphate (Estradurin) administration and a combination of castration and Estradurin administration during the first 12 months of treatment. Estradurin treatment alone (80 mg i.m.l once a month) did not result in any significant changes in the circulating concentrations of FSH, LH and prolactin. Therefore, the clear-cut inhibition of testicular steroidogenesis observed under this kind of treatment does not appear to be due to an inhibition of pituitary gonadotropin secretion, and is most likely due to a direct estrogen effect on Leydig cells. Castration led to grossly elevated serum FSH and LH levels. In this group, serum FSH remained at a high level, whereas LH was close to pretreatment levels 9 months after castration, suggesting differences in pituitary capacity to secrete FSH and LH under these conditions. Concentrations of circulating FSH, and to a lesser extent LH, in the combination treatment group were between those found in the castration and estrogen-only treatment groups, suggesting that the secretion of both gonadotropins can be suppressed by estrogen. No changes in serum prolactin and ACTH concentrations were seen in the three treatment groups.

The role of Inhibin in the control of the prepubertal hypothalamic-pituitary testicular-axis

Testicular function was studied in 9 men (18-32 years) who had received irradiation for Wilm's tumour during childhood. The dose of (scattered) irradiation to the testes ranged from 500-900 rads. 7 subjects had oligo or azoo-spermia (0-5.6 million/ml), 6 of whom had an elevated serum FSH level. One subject showed evidence of Leydig cell dysfunction (raised plasma LH and low testosterone concentration). These results were compared to those in 8 prepubertal boys who several years earlier had received irradiation for abdominal or testicular tumours (dose to the testes 500-3000 rads). In all 8 the serum FSH, LH and testosterone were within the normal prepubertal range. Thus irradiation-induced damage to the germinal epthelium in prepubertal boys produces raised FSH levels after puberty but not before it. We conclude, therefore, that Inhibin has a negligible role in the control of the prepubertal hypothalamic-pituitary-testicular axis and that gonadal control of gonadotrophin secretion changes with sexual maturation.

On the Feedback Actions of Estrogen on Gonadotropin and Prolactin Release in Infantile Female Rats1

A fetoneonatal estradiol-binding plasma protein, often referred to as alpha fetoprotein (AFP), is present in high levels in serum of neonatal rats. The existence of elevated serum FSH levels, in spite of high estrogen titers and the presence of adult type estrogen receptors in the hypothalamus and pituitary, suggests that the lack of a fully expressed estrogen negative feedback in these animals is not due to a decreased function of the receptors, but rather to binding of estrogen to AFP. To evaluate this hypothesis, rats were ovariectomized at day 10 and injected sc daily for 3 days with different doses of estradiol benzoate (Eb), for which AFP has a very high binding affinity, diethylstilbestrol (DES), which binds very weakly to AFP, or ll-β-methoxyethynylestradiol (RU2858), which does not bind to AFP. Only the largest doses of EB (0.05 and 0.10 μg/100 g BW) were effective in preventing the postcastration rise in FSH. The smallest dose (0.0025 μg/100 g BW) of DES significantly reduced the postcastration ...