Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “FSH”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,279 records · Page 71Linked to original sources
PubMed1996

[Ovulation induction with pure FSH in anovulatory patients resistant to clomifene citrate].

The objective was to evaluate the utility of the pure FSH as treatment of women clomiphene-resistant. Seventy two patients clomiphene-resistant were treated with pure FSH. Ovulation induction was started with 75 IU of pure FSH on day 3 of the menstrual cycle, monitoring the follicular growth with transvaginal ultrasonography, additional doses of pure FSH were administered accordingly. Human chorionic gonadotropin (10,000 IU) was administered when the dominant follicle reached a diameter > or = 16 mm. The pregnancy rate per cycle was 18.0%, on the other hand, the cumulate rate of pregnancy was 72.2%. There was not significant difference in the pregnancy rate between patients with primary or secondary infertility. The rate of spontaneous abortions was similar to the general population. As conclusion, it therefore appropriate to offer the treatment with pure FSH to patients clomiphene-resistance. The cases with gonadotropin-resistance, will be candidates to surgical procedures.

Adolescent↗
PubMed1996

[Prognostic value of high FSH concentrations].

Ovarian age is a major determinant of success in assisted reproductive technologies. The number and quality of oocytes retrieved directly depend upon the ovarian reserve. The evaluation of FSH concentration during the first days of the menstrual cycle provides a simple and accurate means of assessing ovarian reserve. Plasma FSH value is correlated with cancellation rate, peak estradiol, number of oocytes retrieved and of the resulting embryos, pregnancy rate, outcome of cryopreservation. However, a poor response to the stimulation treatment is unpredictable in a subgroup of women whose FSH concentration remain within the normal range. Ovarian aging begins several years before any clinical or endocrinological modification. Recurrent FSH determinations may help in predicting a poor response, as a large intercycle FSH variability is correlated with ovarian failure. The value of ovarian reserve tests is presently not fully established.

Age Factors↗
PubMed1996

Catecholamine levels and activity of monoamine oxidase in some hypothalamic structures and in the pineal gland of sheep after administration of FSH.

The influence of hormonal preparations of FSH in a dose of 24 mg (480 IU) on levels of catecholamine (dopamine, norepinephrine and epinephrine) and the activity of their degradation enzyme monoamine oxidase (MAO) in the hypothalamic regions regulating the reproductive system of sheep (area preoptica, eminentia mediana, corpus mamillare) and pineal gland were investigated in the oestrous period employing radiochemical methods. The administration of FSH resulted in significant (p<0.001) increases of dopamine levels in the area preoptica and corpus mamillare of the hypothalamus of sheep as compared to control groups with synchronized oestrus. Hormonal stimulation with FSH increased the levels of hypothalamic norepinephrine in the areas studied and these differences were significant in the eminentia mediana (p<0.05) and corpus mamillare (p<0.05). Significant (p<0.001) changes in epinephrine levels were found in the corpus mamillare and area preoptica (p<0.05). Our results indicate that the administration of FSH caused the most pronounced decrease of MAO activity in corpus mamillare (p<0.001). The pineal gland reacted to the hormonal preparation by decreased levels of norepinephrine and dopamine (p<0.001) and by an increase in MAO activity (p<0.01). We suggest that FSH administration affects catecholamine levels and the activity of monoamine oxidase in the studied areas of the brain of sheep by means of a feedback mechanism.

Animals↗
PubMed1976

In vitro transfer rate of 14C from acetate-1-14C into ovarian steroids in the rat ovary during the estrous cycle and effects of LH and FSH.

Fluctuations of ovarian biosynthetic activity and effects of exogenous LH and FSH on it during the estrous cycle were investigated by measuring in vitro transfer rates of 14C from 14C-1-acetate into progesterone (P), 20 alpha-hydroxy-pregn-4-en-3-one (20 alpha-OH-P) and estrogen (estradiol and estrone, E) in the ovarian homogenates from rats autopsied at 2 hour intervals. The transfer rate of 14C from 14C-1-acetate into P was lowest in the afternoon of estrus and increased from the morning of diestrus 1, making its peaks during the afternoon of diestrus 2 and in the midnight of proestrus. The transfer of 14C into 20 alpha-OH-P was high on the days of diestrus 2 and proestrus with its peak in the afternoon of the latter day. The maximum transfer of 14C into E in the afternoon of proestrus and a high rate in the morning of estrus with relatively low one in the midnight were observed. Exogenously injected LH (150 mug) or FSH (150 mug) was either stimulatory or inhiibitory to the transfer rates of 14C from 14C-1-acetate into ovarian steroids. During day time of diestrus 2 and midnight between proestrus and estrus, the transfer of 14C into P and 20 alpha-OH-P increased by LH, and during day time of proestrus and from the afternoon of estrus to the morning of diestrus 1 decreased. The transfer of 14C into E increased by LH from the afternoon of diestrus 2 to the morning of proestrus, and decreased during the afternoon of proestrus and from the afternoon of estrus to the morning of diestrus 2. Administration of FSH was also stimulatory or inhibitory. The 14C transfer into P and 20 alpha-OH-P increased by FSH from the afternoon of estrus to the morning of proestrus, but in the afternoon of proestrus they decreased. Transfer of 14C into E increased by FSH significantly on the days of diestrus 2 and proestrus, and slightly on the day of estrus, while it decreased in the afternoon of diestrus 1.

Acetates↗
PubMed1998

Coexpression of gonadotropic hormones and their corresponding FSH- and LH/CG-receptors in the human prostate.

BACKGROUND: Benign prostatic hyperplasia (BPH) affects the majority of elderly men, and prostate cancer is the most common male cancer. Prostatic growth and function are thought to be regulated by steroid hormones, primarily androgens and estrogens, but nonandrogenic hormones must also be considered. The increasing evidence of para/autocrine functions of the gonadotropic glycoprotein-hormones (GPH), their allocation to the superfamily of cystine-knot growth factors, and luteinizing hormone (LH)/chorionic gonadotropin (CG)-receptor (R) gene expression in nongonadal tissues led us to investigate intraprostatic GPH and GPH-R gene expression. METHODS AND RESULTS: RT-PCR and subsequent Southern hybridization and/or restriction enzyme analysis of BPH and prostatic adenocarcinoma demonstrated that all three human (h) gonadotropic hormones, i.e., follicle-stimulating hormone (FSH), LH, and CG, as well as the corresponding FSH-R and LH/CG-R, are transcribed intraprostatically. Significant amounts of the alpha and beta subunits of hCG were secreted by short-term primary cultures of human BPH tissues, as detected by highly sensitive and specific time-resolved immunofluorometric assays (IFMAs). CONCLUSIONS: Our data suggest that prostatic- and pituitary-derived GPH act directly on the prostatic gland, particularly FSH via the FSH-R, thereby possibly modulating locally acting key hormones and growth factors involved in BPH development.

Chorionic Gonadotropin↗
PubMed1996

Influence of FSH and hCG on the resumption of meiosis of bovine oocytes surrounded by cumulus cells connected to membrana granulosa.

Cumulus oocyte complexes (COCs) and cumulus oocyte complexes connected to a piece of the membrane granulosa (COCGs) were isolated from bovine antral follicles with a diameter of 2 to 8 mm. After culture of COCGs without gonadotrophic hormones for 22 hr approximately 50% of the oocytes were still in the germinal vesicle (GV) stage. Histology of the COCGs showed that the pieces of the membrana granulosa were free of thecal cells and parts of the basal membrane. This indicates that the membrana granulosa solely inhibits the progression of meiosis. To investigate the effect of gonadotropins on the resumption of meiosis of oocytes from small and medium sized antral follicles, COCs and COCGs were cultured with or without rec-hFSH or hCG. Addition of 0.05 IU rec-hFSH to the culture medium of COCGs resulted in germinal vesicle breakdown in 97.8% of the oocytes compared to 46% in the control group, and an increase of the diameter of the COCs (479 microns vs. 240 microns in the control group). Addition of 0.05 IU hCG to the culture medium had no effect on nuclear maturation (47.2% GV vs. 48.5% GV in the control group) nor on cumulus expansion (246 microns vs. 240 microns in the control group). RT-PCR on cDNA of the follicular wall, cumulus cells, granulosa cells, COCs, and oocytes revealed that mRNA for FSH receptor was present in all cell types except oocytes. mRNA of the LH receptor was detected exclusively in thecal cells. Nucleotide sequence analysis and alignment of the cloned PCR products showed the presence of two isoforms of the FSH receptor mRNA and two isoforms of the LH receptor mRNA. It is concluded that, in vitro, resumption of meiosis of oocytes, originating from small and medium sized antral follicles and meiotically arrested by the membrana granulosa, is triggered by FSH and not by LH. This is supported by the fact that receptors for FSH, but not for LH, are transcribed in the cumulus and granulosa cells of these follicles.

Amino Acid Sequence↗
PubMed2005

Effects of FSH receptor deletion on epididymal tubules and sperm morphology, numbers, and motility.

Follicle stimulating hormone (FSH) interacts with its cognate receptor (R) on Sertoli cells within the testis and plays an important role in the maintenance of spermatogenesis. Male FSH-R knockout (FORKO) mice show fewer Sertoli cells and many that are structurally abnormal and as a consequence fewer germ cells. Lower levels of serum testosterone (T) and androgen binding protein (ABP) also occur, along with reduced fertility. To assess the effects of FSH-R depletion as an outcome of testicular abnormalities, sperm from the cauda epididymidis were counted and examined ultrastructurally. As reduced fertility may also reflect changes to the epididymis, the secondary responses of the epididymis to lower T and ABP levels were also examined by comparing differences in sizes of epididymal tubules in various regions of FORKO and wild type (WT) mice. Sperm motility was evaluated in FORKO mice and compared to that of WT mice by computer assisted sperm analysis (CASA). Quantitatively, the data revealed that epithelial areas of the caput and corpus epididymidis were significantly smaller in FORKO mice compared to WT mice. Cauda epididymal sperm counts in FORKO mice were also much lower than in WT mice. This resulted in changes to 9 out of 14 sperm motility parameters, related mostly to velocity measures, which were significantly lower in the FORKO mice. The greatest change was observed relative to the percent static sperm, which was elevated by 20% in FORKO mice compared to controls. EM analyses revealed major changes to the structure of the heads and tails of cauda luminal sperm in FORKO mice. Taken together these data suggest a key role for the FSH receptor in maintaining Sertoli cells to sustain normal sperm numbers and proper shapes of their heads and tails. In addition, the shrinkage in epididymal epithelial areas observed in FORKO mice likely reflect direct and/or indirect changes in the functions of these cells and their role in promoting sperm motility, which is noticeably altered in FORKO mice.

Animals↗
PubMed2000

Mutations of LH and FSH receptors.

Gonadotropins control male and female gonadal function by acting through specific receptors. The recent description of several mutations in LH and FSH receptors has significantly improved our understanding of the pathophysiology of several sexual disorder. Both gain- and loss-of-function germline mutations leading to constitutive receptor activation or to hormone resistance have been described. The clinical impact of these mutant receptors can be markedly different, depending upon the sex of the affected patient and the degree of functional alteration. Numerous mutations were described in LH receptor gene. Constitutive activation of this receptor leads to male-limited precocious pseudopuberty, whereas hypergonadotropic hypogonadism is the clinical phenotype of LH resistance. On the other hand, few mutations of FSH receptor were described so far. Inactivating mutations of FSH receptor are involved in some cases of hypergonadotropic hypogonadism with a more severe impairment of fertility in female patients. Only one gain-of-function mutation of FSH receptor was reported to maintain fertility in one hypophysectomized man. This review is focused on the known genetic alterations of gonadotropic receptors in humans and their impact on male sexual differentiation and fertility.

Female↗
PubMed2006

Immunohistochemical localization and quantitative assessment of GnRH-, FSH-, and LH-receptor mRNA Expression in canine skin: a powerful tool to study the pathogenesis of side effects after spaying.

It has been proposed that gonadotropins and/or gonadotropin releasing hormone (GnRH) could be involved in the pathophysiology of the side effects after spaying in bitches, such as urinary incontinence and an increased production of a woolly undercoat. In order to provide tools to investigate the role of these hormones in dogs we developed immunohistochemical techniques and real-time RT-PCR to study whether GnRH-, LH-, and FSH-receptors exist in canine skin and urinary bladder. Tissue samples from the skin of the flank region and the ventral midline of the urinary bladder from euthanised dogs were examined. We were able to quantify mRNA expression of GnRH-, FSH-, and LH-receptors in canine skin and bladder biopsies with a high primer efficacy. Immunohistochemical studies showed that GnRH-, FSH-, and LH-receptors are expressed in vessel walls, the epidermis, the hair follicle and in sebaceous and sweat glands in canine skin and in transitional epithelium, and smooth muscle tissue in the urinary bladder. Our data provide the fundamentals to examine the distribution of FSH-, LH-, and GnRH-receptors in canine skin and urinary bladder and to assess gene activity at the transcriptional level by real-time RT-PCR.

Animals↗
PubMed1992

FSH receptor mRNA is expressed stage-dependently during rat spermatogenesis.

In situ hybridization was performed on testicular tissue from adult male Sprague-Dawley rats using cRNA antisense and sense probe of the monkey FSH receptor (FSHR) cDNA to determine the cellular site of synthesis, and possible stage-dependent expression of FSHR mRNA during the cycle of the seminiferous epithelium. Using antisense probe specific binding was first detected in Sertoli cells just prior to sperm release at stage VIII. The strongest specific hybridization signal was found during stages IX and X followed by a decrease of signal intensity in stages XI-XII. No specific binding was found in stages XIII-VII. The sequence of events with the maximum expression of FSHR mRNA in Sertoli cells in stages IX and X, before FSH-binding and FSH-stimulated cAMP production reach maximum values, coincides with a new wave of spermatogenesis and indicates an effect of FSH and spermatogenic cells on the regulation of FSHR mRNA expression.

Animals↗
PubMed1995

The molecular biology of the FSH receptor.

The actions of follicle stimulating hormone (FSH) mediated through its receptor are necessary for the proper functioning of mammalian gonads. The FSH receptor is localized on granulosa cells of the ovary and Sertoli cells of the testis. The expression of the FSH receptor (FSHR) in Sertoli cells varies in vivo as a function of the stage of the cycle of the seminiferous epithelium and in culture as a result of the addition of exogenous hormones. The gene for the FSH receptor is large and has been shown to be related in structure to the genes for luteinizing hormone (LH) receptor and thyroid stimulating hormone (TSH) receptor. The promoter region of the gene for FSHR does not contain a TATA box and has multiple transcriptional start sites. Less than 280 bp of the promoter are sufficient in transient transfection assays to direct expression of the chloramphenicol acetyl transferase gene (CAT) in a number of different cell types including non-gonadal cells. However, the promoter does direct the expression of a marker gene only into testis and ovary of transgenic mice.

Female↗
PubMed2000

Lack of interaction in recombinant human FSH receptor and both TSAb and TSBAb.

Since cross-reactivity of TSH with the human FSH receptor has been reported, in this study we tested the effect of thyroid-stimulating antibody (TSAb) and thyroid stimulation-blocking antibody (TSBAb) on Chinese hamster ovary cells expressing human FSH receptor (CHO-hFSH-R cells). We examined the TSBAb activity of sera from hypothyroid patients who had a positive TBII to determine whether these sera also block the effect of FSH on CHO-hFSH-R cells. Although human FSH I-3 (0.25-16 ng/ml) stimulated the production of intracellular cAMP in CHO-hFSH-R cells with dose-responsive manner, neither TSAb nor TSBAb had such an effect on the cells.

Adult↗
PubMed1996

Expression of biologically active fusion genes encoding the common alpha subunit and either the CG beta or FSH beta subunits: role of a linker sequence.

The gonadotropin/thyrotropin hormone family is characterized by a heterodimeric structure composed of a common alpha subunit non-covalently linked to a hormone-specific beta subunit. The conformation of the heterodimer is essential for controlling secretion, hormone-specific post-translational modifications and signal transduction. Structure-function studies of FSH and the other glycoprotein hormones are often hampered by mutagenesis induced defects in subunit combination. Thus, the ability to overcome the limitation of subunit assembly would expand the range of structure activity relationships that can be performed on these hormones. Here we converted the FSH heterodimer to a single chain by genetically fusing the carboxyl end of the FSH beta subunit to the amino end of the alpha subunit in the presence or absence of a natural linker sequence. In the absence of the CTP linker, the secretion rate was decreased over three fold. (The CTP sequence is the last 28 amino acids of the CG beta sequence and contains four serine-linked oligosaccharides). Unexpectedly however receptor binding/signal transduction was unaffected by absence of the linker. Molecular modelling of the tethers lacking the linker sequence show that the alignment of the alpha/beta domains in the single chain differ substantially from that seen in the heterodimer. These data show that the single chain FSH was secreted efficiently and is biologically active and that the conformation determinants required for secretion and biologic activity are not the same.

Animals↗
PubMed1996

The LH/CG and FSH receptors: different molecular forms and intracellular traffic.

Monoclonal antibodies have been raised against the LH/CG receptor [1] and have allowed to perform immunochemical studies of the receptor in target cells. Three different forms of the LH/CG receptor are physiologically expressed: a mature approximately 85 kDa transmembrane species corresponding to the full length receptor, a approximately 68 kDa high mannose containing species corresponding to a precursor which accumulates inside the cells, and truncated soluble approximately 45-48 kDa molecular weight species corresponding to the variant messanger RNAs generated by alternative splicing. Monoclonal antibodies against the human FSH receptor were also prepared. They allow to observe the existence of two forms of the FSH receptor in the ovaries: a major approximately 87 kDa species corresponding to the mature receptor and a minor approximately 81 kDa species corresponding to a high mannose rich precursor. No variant forms of the receptor corresponding to alternative mRNA transcripts were detected. The transport of hCG was examined in rat testicular microvasculature by electron microscopy and by analyzing the transfer of radiolabeled hormone and antireceptor antibodies. LH/CG receptors were present in endothelial cells and were involved in hormone transcytosis through these cells. Immunocytochemical experiments have shown that the FSH receptor has a polarized expression in the Sertoli cells of the testes whereas the LH/Cg receptor is spread on the surface of thecal granulosa and luteal cells in the ovary and Leydig cells in the testes. To study the mechanism of this polarization FSH, LH and TSH receptors were expressed in polarized MDCK cells. The mechanism of basolateral localization and of transcytosis of the receptors was studied using this model. The effect of hormone, cAMP and agents acting on G proteins was examined.

Animals↗
PubMed2002

Distribution and function of FSH receptor genetic variants in normal men.

Follicle stimulating hormone (FSH) plays a key role in the maintenance of qualitatively and quantitatively normal spermatogenesis. It controls gamete development through Sertoli cells, via binding to its receptor. The influence and importance of FSH receptor (FSHR) variants on Sertoli cell function is not completely understood and remains to be investigated. In this retrospective study, we explored the impact and action of two distinct FSHR isoforms, Thr307/Asn680 and Ala307/Ser680, in a large group of men. This investigation includes 288 normal healthy men, 86 of whom were proven fathers previously studied, and 202 were newly recruited subjects. The FSHR polymorphism at position 680 was analyzed in the whole group, while position 307 was investigated in 150 subjects, both of them by single-stranded conformation polymorphism (SSCP) gel electrophoresis. The distribution frequency for position 680 was 29% for the Asn/Asn, 52% for the Asn-Ser, 19% for the Ser-Ser variant, and for position 307, 27% for the Thr-Thr, 55% for the Ala-Thr, 18% for the Ala-Ala, respectively. Polymorphism combinations that were different from Thr307/Asn680 - Ala307/Ser680 were found in four subjects. When subjects were grouped according to genotype at position 680, no significant differences between basal FSH, testosterone, inhibin B levels and semen parameters were found. This clinical finding demonstrates that, differently from females, in whom a significant correlation between FSHR polymorphism and basal FSH levels was found, the FSHR genotype has no influence on clinical parameters in males.

Base Sequence↗
PubMed2006

Effects of a thyroid-stimulating human monoclonal autoantibody (M22) on functional activity of LH and FSH receptors.

OBJECTIVE: The glycoprotein hormones luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyrotropin (TSH) show low-level cross-reactivity between their respective receptors (R). Patient serum autoantibodies to the thyrotropin receptor (TSHR) do not appear to cross-react with the luteinizing hormone receptor (LHR) or follicle-stimulating hormone receptor (FSHR), although the concentrations of autoantibody with which it is feasible to carry out experiments of this type are limited. Consequently, we have studied the effects of high doses of the thyroid-stimulating human monoclonal autoantibody (M22) on the LHR and FSHR. DESIGN: Chinese Hamster ovary (CHO) cells stably expressing the TSHR, LHR, and FSHR and purified M22 IgG preparations were used in the study. METHODS: CHO-TSHR, CHO-LHR, and CHO-FSHR cells were incubated with bovine TSH (0.1-25mU/mL), human recombinant chorionic gonadotropin (hCG; 0.5-10mU/mL) or human recombinant FSH (100-5000mU/mL) or with M22 IgG (0.001-5.0 microg/mL), and the extracellular cyclic AMP was measured by radioimmunoassay. RESULTS: Cyclic AMP levels increased in a dose-dependent manner after incubation of CHO-TSHR cells with TSH or M22 IgG, and on a molar basis the effects of TSH and M22 were similar. Cyclic AMP stimulation was not detectable in CHO-LHR and CHO-FSHR cells after incubation with M22 IgG, whereas incubation with hCG or FSH, respectively, caused dose-dependent cyclic AMP stimulation. On a molar basis, concentrations of M22 IgG approximately 100x those of FSH causing clear stimulation were ineffective with CHO-FSHR cells. Similarly, molar concentration of M22 IgG 20,000x those of hCG causing clear stimulation had no effect on CHO-LHR cells. CONCLUSIONS: This study shows that at relatively high concentrations, M22 IgG is unable to stimulate cyclic AMP levels in CHO-LHR or CHO-FSHR cells, suggesting that TSHR autoantibodies have greater specificity for the TSHR than TSH itself.

Animals↗
PubMed2001

Mathematical model of FSH-induced cAMP production in ovarian follicles.

During the terminal part of their development, ovarian follicles become totally dependent on gonadotropin supply to pursue their growth and maturation. Both gonadotropins, follicle-stimulating hormone (FSH) and luteining hormone (LH), operate mainly through stimulatory G protein-coupled receptors, their signal being transduced by the activation of the enzyme adenylyl cyclase and the production of second-messenger cAMP. In this paper, we develop a mathematical model of the dynamics of the coupling between FSH receptor stimulation and cAMP synthesis. This model takes the form of a set of nonlinear, ordinary differential equations that describe the changes in the different states of FSH receptors (free, bound, phosphorylated, and internalized), coupling efficiency (activated adenylyl cyclase), and cAMP response. Classical analysis shows that, in the case of constant FSH signal input, the system converges to a unique, stable equilibrium state, whose properties are here investigated. The system also appears to be robust to nonconstant input. Particular attention is given to the influence of biologically relevant parameters on cAMP dynamics.

Algorithms↗
PubMed1982

Measurement of human FSH by radioreceptor assay.

We established a sensitive RRA system for human FSH, employing PMS-treated immature rat ovary. The dissociation constant of the binding of the receptor preparation to NIAMDD human FSH-2 was 1.15 x 10(-10) M. The standard curve was obtained with 0.2-25.6 ng/tube of NIAMDD hFSH-2. Purified hLH, hTSH, and HCG had no significant effect on the binding. When the anterior pituitary homogenates obtained from humans were assayed by this system, the intra-assay and inter-assay coefficients of variation were 11.9% and 13.4% respectively, and the assay values correlated well with those obtained by RIA. This assay is applicable for the measurement of FSH in serum, when the non-specific inhibitor effects of serum are compensated for by the addition of merthiolate and when FSH-free serum is used instead of the buffer for the standard curve. The intra-assay and inter-assay coefficients of variation were 9.31% and 19.7% respectively. The assay values correlated with those obtained by RIA under the same physiological state. The ratio of the assay values RRA/RIA, was dependent upon the physiological state, e.g. 6.29 in men, 3.84 and 4.18 in women at follicular and luteal phase respectively and 2.40 in menopausal women. During the menstrual cycle, our results showed that the value of RRA/RIA derived from serum did not change significantly.

Animals↗