Blood Levels Of FSH Research Articles

The relationship between progestins and gonadotropins during the late luteal phase of the menstrual cycle in rhesus monkeys.

The effects of progesterone on blood levels of FSH and LH during the late luteal and early follicular phase of the cycle were studied in 10 regular cycling rhesus monkeys. Progesterone administered for 8 days in silastic capsules, beginning 12 days after peak concentrations of estrogen in serum, prolonged the luteal phase levels of this hormone in 6 animals. Blood levels of progesterone were not affected in 4 control animals given cholesterol. Throughout two consecutive cycles, progesterone, 20α-hydroxypregn- 4-ene-3-one, estradiol, FSH, and LH were measured by radioimmunoassay at selected intervals. The length of time between the LH peaks in cycle I and II differed significantly (p < 0.05) between animals treated with progesterone (35.8 ± 1.21, SD, days) and those treated with cholesterol (31.0 ± 2.16, SD, days). The concentrations of FSH in the late luteal and early follicular phase of the cycle continued to rise significantly (p < 0.01 by regression analysis) in both treated and control animals in spit...

Quantitative aspects of follicular development in the untreated and PMS-treated cyclic hamster.

AbstractHamsters injected at 0900 on day 1 of the cycle (metestrus) with either 0, 5 or 15 IU pregnant mare's serum (PMS) were killed at 1500 of days 1 to 4 of the cycle and the ovaries prepared for light microscopy and for a quantitative evaluation of follicular development. In the untreated cyclic hamster, the maximal number of preantral follicles with eight or more layers of granulosa cells occurred between the afternoon of day 4 (proestrus) and day 1, coinciding with the highest blood levels of FSH and LH. It is concluded that the elevated preovulatory levels of gonadotropins not only induce the ovulation of the mature antral follicles but at the same time recruit the next set of follicles for development during the new cycle.By the afternoon of day 1, treatment with either 5 or 15 IU PMS recruited more follicles into large preantral and incipient antral stages than in the untreated hamsters. However, by day 2 the pattern of follicular distribution was similar between the 5 IU PMS and untreated group whereas considerably more antral follicles had differentiated in the animals given 15 IU PMS. The ability of 15 IU PMS to elicit superovulation therefore depends on the levels being initially high enough to mature more follicles at critical stages of their development; the prolonged biological half life of PMS then sustains these follicles throughout the cycle.

Gonadotrophins, testosterone and oestrogen levels in relation to ovarian morphology in 11 -hydroxylase deficiency.

ABSTRACT Two siblings, aged 6 years 2 months and 4 years 2 months respectively, with the hypertensive form of congenital virilizing adrenal hyperplasia due to 11β-hydroxylase deficiency are presented. The blood levels of FSH were in the pubertal range and the LH levels were low. Testosterone-like-substances (TLS) were in the normal range for adult males; urinary oestrogens were increased and the bone ages were 15 and 13 years. Pubertal development had begun although suppression therapy was never started, as shown by the pubertal levels of FSH, and the rapid increase of both FSH and LH when the adrenal secretion was suppressed. Polycystic ovaries were observed in both cases. The role of testosterone and derivatives as well as of FSH in the development of polycystic ovaries is discussed.

Influence of progesterone on the pituitary and plasma levels of LH and FSH in the female rat.

In order to study the effects of progesterone on pituitary gonadotrophin levels, the steroid was administered (4 mg/day, subcutaneously) for a period corresponding to the duration of pseudopregnancy (12–14 days) to intact, unilaterally and bilaterally spayed rats (4–15 rats/group). In the bilaterally spayed rats the progesterone treatment was started on the day of ovariectomy, 43 days after ovariectomy or 43 days after ovariectomy + estrogen priming. In all experiments, pituitary levels and in some experiments involving bilaterally spayed rats, blood levels of FSH and LH were determined by HGG augmentation and OAAD methods, respectively. The administration of progesterone to intact and unilaterally spayed rats resulted in increased pituitary LH stores which appeared comparable to those which have been reported to normally occur at proestrus during the estrous cycle. In contrast, pituitary FSH stores in these experiments were increased by more than three-fold (p < .05). Progesterone treatment from the day of bilateral spaying failed to alter ovariectomy-induced increases in pituitary LH and FSH stores but was effective in decreasing postovariectomy rises in the plasma LH and FSH. In the long-term spayed rats, whether primed with estrogen or not, progesterone failed to alter pituitary stores of LH and FSH. It appears that progesterone, at least under the experimental conditions employed, in addition to decreasing the release of LH, also decreases its synthesis in the pituitary. To some extent, it is postulated, the same may be true with regard to FSH.