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1.
On Days 28-30 of age, hypophysectomized rats were treated with oestradiol-17 beta (0.1 mg/day) and/or clomiphene citrate (0.1 mg/day). Subsequent treatment with PMSG (10 i.u., on Day 31) and hCG (10 i.u., on Day 33) was identical for all animals. Rats were killed on Day 34. Treatment with oestradiol-17 beta alone resulted in ovulations of 45.1 +/- 5.5 oocytes/rat (mean +/- s.e.m.). There were no ovulations among animals treated with clomiphene citrate alone but treatment with oestradiol-17 beta and clomiphene citrate resulted in a significant (P less than 0.05) reduction (23.1 +/- 7.6 oocytes/rat) in ovulatory response. Similarly, ovarian weights and serum progesterone concentrations were highest in the oestradiol-17 beta-treated rats, intermediate in those given oestradiol plus clomiphene citrate and the lowest in rats receiving clomiphene citrate alone. We suggest that clomiphene citrate exerts direct ovarian antiovulatory and oestrogen-antagonist actions.  相似文献   

2.
The influence of clomiphene citrate on follicle-stimulating-hormone (FSH) and estradiol-induced growth of ovarian follicles and oviducts in the lizard A. carolinensis was studies. In Experiment 1 lizards received 14 daily injections of either saline, clomiphene (1, 10 or 20 mcg), or FSH (1 or 10 mcg) or combined clomiphene-FSH treatment. In Experiment 2, adult lizards with hypertrophied, vitellogenic ovaries, and enlarged oviducts, weres adenohypophysectomized and treated with a daily dose of .05 ml of either saline, saline plus 5 mcg clomiphene, saline plus 10 mcg FSH, saline plus 10 mcg estradiol-17beta, or FSH plus clomiphene or estradiol plus clomiphene. FSH increased follicle size in previtellogenic ovaries. Injection of 1 mcg clomiphene reduces the effects of FSH. 20 mcg clomiphene given alone stimulated the growth of larger follicles. Clomiphene blocked FSH-induced appearance or maintenance of large (less than 2.0 mm) vitellogenic follicles. It blocked FSH gains in oviductal weight and well as stimulated growth of small previtellic follicles. Estradiol-induced follicular and oviductal growth was uneffected by clomiphene. While low doses of clomiphene are antiestrogenic they are unable to combat the effects of high dose estradiol.  相似文献   

3.
The effect of unilateral ovariectomy on ovulation rates in immature mice was studied. Ovulations were induced by injecting PMSG and hCG and their number was determined by counting tubal oocytes. A 2--3-fold increase in number of ovulations per ovary was observed after unilateral ovariectomy, and daily injections of progesterone abolished this ovulatory compensation. No significant increase in serum concentrations of immunoreactive FSH and LH was observed at 4, 8, 32 and 51 h after unilateral ovariectomy. Progesterone treatment lowered FSH levels at all times, while LH was unaffected. In intact mice, ovarian sensitivity to PMSG and hCG was not substantially affected by progesterone. Ovulatory compensation in immature gonadotrophin-injected mice appears to arise through a negative feedback mechanism and transiently increased secretion of pituitary gonadotrophin rather than through a greater utilization of a fixed amount of gonadotrophin.  相似文献   

4.
Steroidogenesis was compared between luteal cells from immature pseudopregnant (PSP) rats induced by either 5 IU pregnant mare serum gonadotropin (PMSG) alone or 50 IU PMSG combined with 25 IU human chorionic gonadotropin (hCG). It was also determined whether differences in steroidogenesis existed when the entire ovary (ovarian cells) or just luteal cells from Day 4 PSP rats were exposed in vitro to lipoproteins or 25-hydroxycholesterol (25-OH chol). In the absence of luteinizing hormone (LH), basal steroid accumulation, especially progesterone (P4) was around fourfold greater in luteal cells from rats treated with PMSG alone than from rats receiving PMSG-hCG. However, serum P4 and LH were about fivefold greater in the latter group. It is therefore likely that net cellular cholesterol uptake per luteal cell is lower in the PMSG-hCG treated rats, but this is offset by a much greater mass and number of corpora lutea. Lipoproteins (HDL and LDL) and 25-OH chol stimulated in vitro luteal steroidogenesis from rats treated with PMSG alone or PMSG-hCG, and their responses were virtually identical. Therefore, luteal steroidogenesis in the rat always depends on exogenous cholesterol even though treatment in the preovulatory period with PMS or PMSG-hCG and serum LH and follicle-stimulating hormone (FSH) levels on Day 4 PSP are very different. When ovarian cells from PMSG-hCG treated rats were incubated with LH plus HDL or 25-OHP, the production of 20 alpha-DHP was considerably greater than luteal cell production which may be due to a contribution from nonluteal cells. Indeed, about 30% of the cells in the PMSG-hCG group represent nonluteal components as estimated by weight and deoxyribonucleic acid content.  相似文献   

5.
《Theriogenology》1986,26(6):749-755
A study was undertaken to induce estrus among 15 non-cyclic Murrah buffalo heifers at a relatively early age of 2.5 to 3 yr by progesterone releasing intravaginal device (PRID) application. On Day 13, the PRID was removed and the animals were divided into two groups (A and B). Group B received 1000 IU of pregnant mare serum gonadotrophin (PMSG) intramuscularly (i.m.) immediately after removal of the PRID, whereas Group A was given no further treatment. Circulating gonadotrophin profiles (luteinizing hormone (LH) and follicle stimulating hormone (FSH) were quantified during and after the PRID treatment, as well as during the induced estrous cycle. LH and FSH levels before, during, and after PRID treatment were in the range of 0.5 to 3.0 ng/ml and 10 to 45 ng/ml, respectively, and could be considered basal levels. The peak FSH levels of Group B (PRID + PMSG) during estrus ranged from 69.44 to 337.06 ng/ml, much higher than the levels recorded in Group A (PRID). None of the animals in Group A showed peak LH levels during estrus, whereas two animals in Group B had peak LH levels of 15.84 and 16.93 ng/ml at 0 h and 12 h after detection of estrus. The higher LH and FSH levels obtained in Group B animals compared with Group A animals was possibly due to the superimposed effect of PMSG over PRID. All of the 14 animals exhibited estrus. None of the animals in Group A conceived whereas three out of seven animals in Group B conceived, indicating that PMSG following PRID resulted in ovulatory estrus.  相似文献   

6.
In an attempt to elucidate the mechanism of suppressive action of glucocorticoids on the hypothalamo-pituitary-ovarian axis, we studied the effects of short-term high dose dexamethasone administration of the LH and FSH responses to LHRH and to clomiphene in healthy women with normal menstrual cycles. Seven women, 21--35 years of age, received 100 micrograms of LHRH i.v. on day 6 of two consecutive menstrual cycles, once with and once without pre-treatment with dexamethasone 2 mg orally every 6 hrs. on days 2 through 5 of the menstrual cycle. Seven other women (ages 21--35 years) received clomiphene citrate 100 mg on days 2 through 5 of their menstrual cycle, once with and once without simultaneous administration of dexamethasone 2 mg orally every 6 h. The administration of dexamethasone suppressed baseline serum levels of LH and FSH and blunted LH and FSH response to both LHRH and clomiphene. The results indicate that short-term administration of pharmacological doses of glucocorticoids suppress the secretion of LH and FSH by a direct effect on the anterior pituitary and possibly by an effect at the hypothalamic level with inhibition of the release of LHRH.  相似文献   

7.
Almeida AP 《Theriogenology》1987,27(2):329-335
A comparison between different superovulatory treatments in dairy cattle was carried out at a commercial embryo transfer unit in Israel. Both pregnant mare serum gonadotrophin (PMSG) and follicle stimulating hormone (FSH) were used, either alone or combined with Syncromate B (SMB). The use of PMSG + SMB significantly decreased the number of corpora lutea present at the time of embryo collection 7 d after insemination, as compared with other treatment regimens. Consequently, a significantly lower number of ova was found in those animals treated with PMSG + SMB. Better superovulatory responses were obtained when FSH, rather than PMSG, was used, regardless of whether they were administered alone or combined with SMB. It was clear that the use of SMB combined either with PMSG or FSH resulted in poorer responses than when either gonadotrophin was used alone.  相似文献   

8.
Baseline serum levels of progesterone and total immunoreactive estrogens were determined for intact and ovariectomized captive female Atlantic bottlenose dolphins (Tursiops truncatus), as well as newly captured wild adult females. Stimulation of ovarian follicular growth and ovulation was attempted by intramuscular injection of pregnant mare's serum gonadotropin (PMSG). High doses of PMSG were required to increase serum estrogen levels. When PMSG was followed by an injection of human chorionic gonadotropin (hCG), ovulation was presumed to have occurred as indicated by subsequent high levels of serum progesterone. From these observations, it appears that 1) females with progesterone levels greater than 3000 pg/ml over an extended period are pregnant, 2) Tursiops truncatus is capable of spontaneous ovulation in captivity without gonadotropin therapy, 3) captive female dolphins, although relatively resistant to PMSG, can be induced to ovulate using a combination of high intramuscular-injected doses of PMSG followed by hCG, and 4) spontaneous ovulation is likely to follow an induced ovulation.  相似文献   

9.
Polycystic ovary syndrome [PCOS] is the commonest cause of anovulatory infertility. Treatment modes available are numerous mainly relying on ovarian stimulation with FSH, a reduction in insulin concentrations and a decrease in LH levels as the basis of the therapeutic principles. Clomiphene citrate is still the first line treatment and if unsuccessful is usually followed by direct FSH stimulation. This should be given in a low dose protocol, essential to avoid the otherwise prevalent complications of ovarian hyperstimulation syndrome and multiple pregnancies. The addition of a GnRH agonists, while very useful during IVF/ET, adds little to ovulation induction success whereas the position of GnRH antagonists is not yet clear. Hyperinsulinemia is the commonest contributor to the state of anovulation and its reduction, by weight loss or insulin sensitizing agents such as metformin, will alone often restore ovulation or will improve results when used in combination with other agents. Laparoscopic ovarian drilling is proving equally as successful as FSH for the induction of ovulation, particularly in thin patients with high LH concentrations. Aromatase inhibitors are presently being examined and may replace clomiphene in the future. When all else has failed, IVF/ET produces excellent results. In conclusion, there are very few women suffering from anovulatory infertility associated with PCOS who cannot be successfully treated today.  相似文献   

10.
Follicular stimulation protocols using pregnant mares' serum gonadotropin (PMSG) or a follicle-stimulating hormone (FSH) preparation were compared to evaluate the yield and quality of embryos obtained from immature rats. Rats received a superovulatory dose of PMSG (401U), a nonsuperovulatory dose of the same gonadotrophin (4 IU), or a continu ous s.c. infusion over a 72-h period with a purified FSH preparation containing an opti mum ratio of luteinizing hormone (LH): FSH (FSH-hCG). The females were caged with fertile males on the evening of the 3rd day of gonadotropin treatment and scored for the occurrence of mating on the next morning; subgroups were killed on days 1–4 of preg-nancy. High fertilization rates were observed in rats treated with 4 IU PMSG (84.1%) and in rats infused with FSH-hCG (91.0%); however, a much lower fertilization rate was observed following treatment with 40 IU PMSG (41.5%). From median ovulation rates of 9 and 79 in rats treated with 4 IU PMSG and in rats infused with FSH-hCG, medians of 8 and 69 embryos, respectively, were recovered from reproductive tracts flushed on day 4 of pregnancy, from which 75% were morulae or blastocysts; in contrast, from a median ovu lation rate of 42.5, a median of only 12 embryos was recovered on day 3 of pregnancy following superovulation with 40 IU PMSG of which 80% were degenerate ova. Serum steroid profiles during the first 4 days of pregnancy differed significantly among treatment groups, the major differences being in substantially elevated levels of estradiol and andro-gens on days 1–3 in rats receiving the high (40 IU) dose of PMSG. Levels of these steroids in rats superovulated with the FSH-hCG infusion regimen were only marginally elevated above levels observed in rats treated with the low (4 IU) nonsuperovulatory dose of PMSG. Consistent with high ovulation rates, serum progesterone levels rose to considera bly higher levels during the period in both superovulated groups than in animals receiving the low, nonsuperovulatory dose of PMSG. This work describes a novel method to superovulate rate (FSH-hCG) leading to high yields of normally developing embryos at all preimplantation stages and illustrates the close association between high yield of emyryos and low levels of circulating andorgens and estradiol-17β during the preimplantation period.  相似文献   

11.
A culture system has been used to study the effect of PMSG in vivo pretreatment and androgens on the in vitro secretion of progesterone from avian granulosa cells. PMSG in vivo pretreated cells secreted greater amounts of progesterone than did cells obtained from untreated hens. Testosterone and 5-alpha-dihydrotestosterone significantly increased basal progesterone secretion in PMSG pretreated cells as well as in granulosa cells harvested from non-treated hens. Testosterone or 5 alpha-dihydrotestosterone in combination with FSH or LH were additive and never resulted in a synergistic stimulation of progesterone secretion.  相似文献   

12.
Effects of gonadotropins on the maturation of isolated oocytes and production of progesterone by porcine ovarian follicles from gonadotropin treated gilts have been studied in vitro. The addition of gonadotropins (2 I. U./ml, PMSG, HGC or 2 mg/ml FSH) to the culture medium resulted in increasing the number (84 - 90 %) of isolated oocytes which reached metaphase II. Expansion of the whole cumulus mass was observed only in media containing PMSG, whereas FSH or HCG alone did not cause these marked changes in the cumulus cells. Denudation of the eggs prior to culture gave no significant differences in the maturation rates between oocytes cultured in media with or without gonadotropins. In vitro maturation of follicle-enclosed oocytes took place only in HCG treated animals. Removing the ovary at 15 or 60 minutes after intravenous HCG administration induced oocyte maturation only in 22% and 17% respectively. A sharp increase in the number of oocytes which resume meiosis during follicle culture was observed 4 hours after HCG injection (84 %) and all of the oocytes of the gilts ovariectomized at 8 hours after HCG injection matured during the culture period. The progesterone production of isolated follicles from control gilts (only PMSG injected) increased slowly during a 96-hour culture period (from 48 to 240 ng progesterone/follicle), whereas the secretion of progesterone was drastically increased after a 15 minute interval between HCG injection and ovariectomy (from 42 to 950 ng progesterone/follicle). Follicles removed 24 hours after HCG injection showed a further increase in steroid production (2000 ng progesterone/follicle) and consistently secreted large amounts of progesterone during the culture period.  相似文献   

13.
Attempts were made to examine progesterone levels during pregnancy block, first initiated by pheromones and then by the injection of pregnant mare serum gonadotropin (PMSG). The proximity of a strange male inhibits the usual increase in progesterone levels, resulting in no activation of the corpora lutea, from the estrous cycle to the pregnancy. Strain differences were observed in the imitation of pregnancy block by the injection of PMSG. The C3H and BALB/c strains required much smaller doses of PMSG for pregnancy block than the C57BL/6 strain did. The changes of progesterone observed in pregnancy block initiated by PMSG were slightly different from that caused by the proximity of the strange male: The progesterone levels temporally increased on the day following the injection of PMSG and then decreased on day 4 in the PMSG-treated group. These results suggest that PMSG imitates the effect of the proximate strange male in the pregnancy block.  相似文献   

14.
1. A study was conducted on the chacma baboon, Papio ursinus with three ovulation induction agents in an effort to define a preferential stimulatory protocol with regards to the number and quality of oocytes obtained. 2. Three folliculogenic agents applied in four stimulatory protocol regimens comprised clomiphene citrate in a high (100 mg/day) and low (50 mg/day) dosage, a combination of clomiphene citrate and pregnant mare serum, and human menopausal gonadotropin. 3. A total of 159 oocytes were aspirated by laparotomy from 10 baboon females in 20 induced cycles with an average of 8.0 +/- 5.4 oocytes per aspiration. 4. The highest mean number of oocytes (11.3 +/- 6.7) were obtained with the clomiphene/pregnant mare serum gonadotropin combination. 5. The best fertilization rate was obtained with clomiphene 50 mg. 6. The highest incidence of oocytic cleavage and embryo transfer were achieved with human menopausal gonadotropin (14.8%).  相似文献   

15.
Follicles were sampled at three different times after treatment with 1200 iu pregnant mares' serum gonadotrophin (PMSG) or 12 mg ovine follicle-stimulating hormone (FSH), and from untreated control animals. The meiotic status and protein synthesis of the oocyte from each follicle was determined and correlated with the intrafollicular concentration of oestradiol and progesterone. Significantly higher amounts of oestradiol were present in PMSG-treated animals at sponge withdrawal than in FSH-treated and control goats. Twenty hours later, both oestradiol and progesterone concentrations in the PMSG group were higher than those in the FSH group, and were equivalent to control animals at the onset of oestrus. At 18 h after the administration of human chorionic gonadotrophin (hCG), oestradiol decreased markedly in all three treatment groups, whereas progesterone remained significantly higher in PMSG-treated follicles. Although these high concentrations of intrafollicular steroids were associated with a higher incidence of premature condensation of chromatin in oocytes, the two events were not causally related. Moreover, cytoplasmic maturation was not prematurely activated in these oocytes and a changed pattern of protein synthesis was observed in oocytes from all three treatment groups after the hCG injection. Whereas disturbances in follicular steroidogenesis of oestradiol and progesterone occur in vivo in goats superovulated with PMSG, they do not underlie the premature activation of the initial stages of nuclear maturation in oocytes but are associated with normal cytoplasmic maturation.  相似文献   

16.
Goats in Group A were pretreated for 9 days with a synthetic progestagen, administered via intravaginal sponge, and 1000 i.u. PMSG s.c. on Day 12 of the oestrous cycle. Goats in Group B had the same PMSG treatment, but not the progestagen pretreatment. Group C goats received a s.c. twice daily injection of a porcine FSH preparation (8 mg on Day 12, 4 mg Day 13, 2 mg Day 14 and 1 mg Day 15). Oestrus was synchronized in all animals by 50 micrograms cloprostenol, 2 days after the start of gonadotrophin treatment. The vaginal progestagen sponges were removed from Group A at the same time. Mean ovulation rate was slightly higher in FSH-treated than in the PMSG-treated animals, whereas the incidence of large follicles that failed to ovulate was significantly elevated in PMSG-treated animals in Group B. More goats in Groups A and B than in Group C exhibited premature luteal failure. Progestagen pretreatment appeared to suppress both follicular and luteal activity, as indicated by numbers of large non-ovulating follicles and by the magnitude and duration of elevated plasma oestradiol levels following PMSG stimulation, and by decreased plasma progesterone levels before and after PMSG treatment. Oestrogenic response to FSH was considerably less than that to PMSG, as indicated both by a considerably shorter duration of elevation of circulating oestradiol levels during the peri-ovulatory period, and by lower maximal oestradiol levels. Differences in the ovarian responses to PMSG and FSH may be attributed primarily to differences in the biological half-life of each preparation.  相似文献   

17.
M J Hosie  C R Murphy 《Acta anatomica》1992,145(2):175-178
Scanning electron microscopy was used to evaluate the uterine luminal epithelium from ovariectomized rats treated with a single minimal physiological dose of clomiphene citrate, oestradiol-17 beta or progesterone. It was found that clomiphene treatment produced some ultrastructural surface features which were similar to those seen with both oestrogen and progesterone treatment, but in addition it produced features unique to clomiphene treatment.  相似文献   

18.
This study was designed to investigate the endocrinological variations induced in anestrous goats by means of different hormonal stimulations. Twenty goats were divided into four groups and, after treatment for 21 days with fluorogestone acetate (FGA) in vaginal sponges, were treated as follows: (1) vehicle; (2) 500 LU. pregnant mare serum gonadotropin (PMSG) 48 h before sponge removal (s.r.); (3) 500 LU. PMSG 48 h before s.r. and 1 μg gonadotropin-releasing hormone (GnRH) every 3 h for 8 times beginning 3 h before s.r. and (4) an ampoule of human menopausal gonadotropin (HMG) equivalent to 300 LU. luteinizing hormone (LH)-like and 300 LU. follicle-stimulating hormone (FSH)-like activity at s.r. Progesterone, estradiol 17β (E2), LH, FSH and prolactin (PRL) plasma variations were analyzed by validated radioimmunoassays. The stimulation of anestrous goats with FGA alone was inadequate to induce either behavioural estrus or variations in the endocrine pattern. All the other treatments (PMSG, PMSG+ GnRH, HMG) induced an increased in estradiol 17β concentration; the highest E2 levels were induced by PMSG + GnRH treatment. The E2 peaks were followed by LH and FSH surges, which occurred at different times depending on the treatments: the LH peak was significantly (P < 0.001) delayed in HMG-treated does compared with PMSG-GnRH-treated animals. Administration of PMSG alone was not adequate to induce a satisfactory synchronization of the LH peak. No relationship seems to exist between PRL plasma variations and estrus-related endocrine patterns.  相似文献   

19.
摘要 目的:探讨复方玄驹胶囊联合枸橼酸氯米芬和维生素E对男性肾阳虚型不育症的治疗效果。方法:选择2017年1月-2019年12月于我院就诊并辨证为肾阳虚型男性不育症患者120例,采用随机数字表法分为研究组和对照组。对照组58例患者给予枸椽酸氯米芬和维生素E治疗,研究组62例患者在此基础上加用复方玄驹胶囊,比较两组临床疗效、治疗前后精子形态正常率、精液量、精子密度、前向运动率、精子液化时间、睾酮(testosterone,T)、黄体生成激素(luteotropic hormone,LH)、卵泡刺激素(follicle stimulatin hormone,FSH)及雌二醇(17β-estrodiol,E2)水平的变化。结果:治疗后,研究组患者的总有效率为85.48 %,显著高于对照组(72.41 %,P<0.05)。与治疗前相比,两组患者精子形态正常率、精液量、精子密度和前向运动率均显著升高,而精子液化时间明显缩短(P<0.05),研究组患者精子形态正常率、精液量、精子密度和前向运动率均显著高于对照组,而精子液化时间较对照组显著缩短(P<0.05)。与治疗前相比,两组患者血清T、LH、FSH水平显著增加,E2水平无明显变化;与对照组相比,研究组血清LH水平显著增加(P<0.05),T和FSH水平无显著差异。结论:复方玄驹胶囊联合枸橼酸氯米芬和维生素E对男性肾阳虚型不育症患者有较好的疗效,可显著提高精子质量,改善患者生殖激素水平。  相似文献   

20.
High serum follicle stimulating hormone (FSH) values are consistent with ovarian failure. We studied the progress of 67 women aged under 35 years with oligomenorrhoea or secondary amenorrhoea in whom the serum FSH value was greater than 20 U/1. Twenty-four patients remained amenorrhoeic, but 17 ovulated and six conceived, two on two occasions. Coincident mean serum luteinising hormone (LH) concentrations were significantly lower and mean total urinary oestrogen concentrations were significantly higher in patients who subsequently ovulated, but the degree of increase in FSH did not correlate well with later ovarian function. Treatment with oestrogens, clomiphene citrate, human pituitary gonadotrophin, and bromocriptine was of no benefit in inducing an ovarian response while FSH concentrations remained raised. Our results suggest that a considerable proportion of younger women with ovulatory disorders associated with FSH values in the menopausal range will spontaneously resume ovulation and some will conceive.  相似文献   

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