Periapical bone loss is one of the prominent pathological and clinical features of periapical periodontitis. Previous studies have demonstrated that follicle‑stimulating hormone (FSH) could directly affect skeletal remodelling by stimulating the formation and the function of osteoclasts in vitro and in vivo. However, the effect of FSH on periapical bone loss remained to be fully elucidated. In ...

AIM To analyze factors influencing the efficacy of hormonal suppression of spermatogenesis for male contraception. METHODS A nested case-control study was conducted, involving 43 subjects, who did not achieve azoospermia or severe oligozoospermia when given monthly injections of 500 mg testosterone undecanoate (TU), defined as partial suppressors compared with 855 subjects who had suppressed ...

BACKGROUND Follicle-stimulating hormone (FSH), a member of gonadotropin family, is critical for follicular maturation and ovarian steroidogenesis. Serum FSH levels are known to fluctuate during different phases of menstrual cycle in premenopausal women, and increase considerably after the menopause as a result of ovarian function cessation. There is little existing evidence to guide researchers...

It is recognised that ovarian factors, including steroid and protein hormones, are critical in the feedback regulation of pituitary gonadotropins; however, their individual contributions are less defined. The aim of this study was to explore the reciprocal relationships between ovarian and pituitary hormones across the normal ovulatory menstrual cycle as women age. FSH, LH, oestradiol, progeste...

BACKGROUND Use of letrozole, a selective inhibitor of aromatase, reduces the gonadotrophin dose required to induce follicular maturation. We evaluated whether incorporation of letrozole could be an effective low-cost IVF protocol for poor responders. METHODS A randomized, controlled, single-blind trial was conducted in the Assisted Reproduction Unit, Institute of Reproductive Medicine, Kolkat...

To investigate a mode and a site of action of inhibin on FSH and LH secretion, in vivo and in vitro effects of porcine follicular fluid (PFF) on FSH and LH secretion were studied in male rats. PFF administered i.v. suppressed basal FSH levels for 1-8 hr, but did not alter LH levels. On the contrary, PFF given either 1 or 6 hr in advance, suppressed LH-RH stimulated LH responses as well as LH-RH...

Postmenopausal osteoporosis, a global public health problem, has for decades been attributed solely to declining estrogen levels. Although FSH levels rise sharply in parallel, a direct effect of FSH on the skeleton has never been explored. We show that FSH is required for hypogonadal bone loss. Neither FSHbeta nor FSH receptor (FSHR) null mice have bone loss despite severe hypogonadism. Bone ma...

In order to elucidate the mechanism of thyroid hormone action on the ovary, direct effects of L-thyroxine (T4) or L-triiodothyronine (T3) on steroidogenic enzyme induction were investigated in vitro using a monolayer culture system of porcine granulosa cells obtained from small follicles. The cells were cultured in the absence or presence of porcine FSH (20ng/ml) for 6 days, with or without T4 ...

The effect of volume and frequency of administration of porcine follicular fluid (pFF) on FSH concentration was determined in mature gilts during the period of the secondary FSH surge (d 0 to 5; d 0 = onset of estrus) and following withdrawal of pFF (d 5.5 to 9). Crossbred gilts (n = 14) were randomized in a 3 x 2 factorial treatment design involving three doses of pFF (0, 5, or 10 ml) and once...

The effect of follicle stimulating hormone (FSH) treatment on the pituitary response to gonadotrophin-releasing hormone (GnRH) was studied in rats in various reproductive conditions. A 3-day treatment of cycling rats with FSH (Metrodin; 10 IU/injection) lowered the spontaneous pre-ovulatory. LH-surge and suppressed the pituitary luteinizing hormone (LH) response to GnRH. FSH also suppressed the...