LH Values Research Articles

Pulsatile Luteinizing Hormone Secretion in Women with Polycystic Ovary Syndrome under Clomiphene Citrate. Differences between Responders and Nonrespondersa , b)

Although administration of Clomiphene Citrate (CC) is an effective therapy for ovulation induction in PCO patients, 15 to 20% of PCO patients do not ovulate following CC treatment. The aim of this study was to compare the endocrine dynamics (LH pulsatile pattern, FSH and steroid hormone changes) in 6 patients who ovulated (PCOS) and 6 PCO patients who did not ovulate in response to CC (PCOR). Blood was collected at 15 min intervals for 4 hr on day 9 of the first menstrual cycle (control cycle) and on day 9 of the following (treatment) cycle. In this cycle all women received 100 mg CC/day from day 5 to day 9. LH was determined in all samples whereas FSH and estradiol were measured every 60 min. No significant differences were observed regarding the age, body mass index, degree of hirsutism, ovarian volumes and basal levels of reproductive hormones between both groups of PCO women. During the control cycle, the LH pulse amplitude and transverse LH mean concentrations in PCOR patients were higher than in PCOR patients whereas the LH pulse frequency was similar in both groups. No difference was found in FSH and estradiol values between both groups. Compared to the control cycle, PCOR patients showed no change in the pulse amplitudes and no difference in LH, FSH and estradiol values following CC treatment. In contrast, during the CC therapy in PCOS patients an increase in the LH amplitude (p less than 0.05), the transverse mean LH concentration (p less than 0.05), FSH and estradiol was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of Football on the Pituitary-Testicular Axis (PTA): Differences between Professional and Non-Professional Soccer Players

Basal levels of LH, FSH, PRL and T, as well as LH, FSH and PRL relative maximum responses (RMRs = peak values/basal values) to an iv bolus of GnRH (0.1 mg) plus TRH (0.2 mg) were evaluated in 7 professional soccer players (PSP) examined on 3 occasions: after a 30 days rest period and 14-15 h from the end of both a customary training session and a strenuous football match, performed at the end of a 3 months regular training program. In 5 out of the 7 PSP a semen analysis was carried out after each endocrine evaluation. The results were compared with those obtained in 10 non-professional soccer players (NPSP) subjected to a similar study protocol, and with the data from 10 healthy, sedentary men. Basal LH values in the rest period were significantly higher (P less than 0.05) in PSP than in control men, whereas LH RMR and sperm motility were significantly lower (P less than 0.02) in the former group. No significant differences in basal hormone concentration and in the RMRs to GnRH-TRH were observed between PSP and NPSP. The training session performed by the PSP after 3 months of regular training did not significantly affect the hormonal parameters. In contrast, the football match induced a significant increase in PRL basal levels (P less than 0.02 vs. controls) and a significant fall in PRL RMR (P less than 0.02 vs. controls).(ABSTRACT TRUNCATED AT 250 WORDS)

Naloxone stimulation test in women with hypothalamic amenorrhea: a preliminary report.

We researched the possibility of the induction of ovulation by means of chronic opioid receptor blockade in 4 women with hypothalamic amenorrhea. Daily 4 mg naloxone were given as a bolus injection intravenously. By means of continuous determination of LH, FSH, 17-beta-estradiol (E2) and progesterone as well as of sonographic folliculometry follicular growth and subsequent ovulation should have been proved. Neither we found alterations of the basal values of LH, FSH, E2 and progesterone, nor we observed a follicular growth. These results lead us to the conclusion to put a naloxone stimulation test before further therapy. In this way opioid mediated hypothalamic ovarian insufficiencies can be registered and a therapy optimum can be reached early.

Reproductive hormonal responses to maximal exercise in endurance-trained men with low resting testosterone levels.

A cross-sectional study was conducted to compare the changes from rest and in response to a maximal exercise bout for select reproductive hormones between age matched groups of endurance trained (ET; distance runners) men with low resting testosterone and untrained (UT) men. Both ET and UT men completed two evaluation sessions: (a) resting hormonal profiling, and (b) a maximal treadmill exercise test to exhaustion. Serial blood samples were taken for four hours at each of the evaluation sessions. Resting and exercise hormonal concentrations were plotted and the area under the response curve (AUC) measured. Percentage change in AUC values were also calculated and compared (exercise vs. resting AUC values). Resting testosterone (16.6 +/- 2.4 vs. 23.9 +/- 3.1 nmol x 1(-1)) and prolactin (3.3 +/- 1.4 vs. 6.0 +/- 2.0 micrograms x 1(-1)) concentrations in the ET men were significantly lower (p < 0.05) than those in the UT men. All other resting hormonal levels did not differ between the groups (p > 0.05). Exercise produced a significant increase (p < 0.05) in the ET men for testosterone, LH, and prolactin AUC values, when compared to resting values. In the UT men the only significant change was a reduction (p < 0.05) in the exercise LH AUC versus the resting AUC value. AUC percentage change values showed between-group differences (p < 0.05) for testosterone, LH and prolactin. The level of change in each of these hormones was found to be greater in the ET than UT group (approximately 20 to 75%). The hormonal changes of the UT men were viewed as "control--reference" responses within a functioning hypothalamo-pituitary-testicular regulatory axis; therefore, it was concluded that the ET men displayed an "atypical" response to exercise to that of UT men relative to this axis.

Effect of an OT antagonist on the control of the midcycle LH surge in women

Data in women regarding the role of OT in LH secretion during the LH surge are conflicting. As in previous studies blood samples for LH measurements were taken infrequently, we re-examined this matter in women with a fully characterized midcycle LH surge. Normal women were studied over two cycles. When the dominant follicle reached a diameter of either 16-17 mm (Group 1) or 18-19 mm (Group 2), the women were infused intravenously for 3 h with normal saline (cycle-1) or atosiban (cycle-2). Fifteen women (10 in group 1 and 5 in group 2) aged 23-35 years. Blood samples were obtained every 6 h to characterize the midcycle LH surge. The time interval (mean +/- SEM) from the start of the infusion to the onset of the LH surge in the two cycles was 46.8 +/- 4.8 and 45.6 +/- 9.6 h in group 1 and 6.0 +/- 2.4 and 7.5 +/- 2.8 h, respectively, in group 2. LH values during the LH surge were similar in the two cycles except in group 1 at the point of 30 h at which LH value in cycle-2 (41.2 +/- 4.6 mIU/ml) was significantly lower than in cycle-1 (52.8 +/- 3.4 mIU/ml, P < 0.05). Nevertheless, in each group, the area under the curve for LH was similar in the two cycles. Antagonism of endogenous OT action by atosiban does not alter the LH profile during a fully characterized midcycle LH surge, suggesting that OT is not a major regulator of LH secretion in women.

Investigation of the hormonal axis hypothalamus-pituitary-gonads in 20 dialyzed men. GnRH-test in dialyzed men.

20 male patients suffering from end-stage chronic renal failure and maintained on hemodialysis were investigated for pituitary response to GnRH. The GnRH-Test was performed simultaneously with hemodialysis; however, hemodialysis was started 60 min. after the injection of GnRH. Basal values of LH and FSH were significantly higher (P less than 0.0001 and 0.005, respectively) than the normal range, while basal values of testosterone were in the subnormal range or depressed (P less than 0.0001). Poststimulatory values of LH were significantly lower (P less than 0.01) than normal and--other than normal--did not decline within 180 min. following injection of GnRH (P less than 0.001). The same pattern was seen for FSH, however, no statistical significance could be secured. Testosteron was elevated 30 min. after stimulation with GnRH (P less than 0.001).

Klinische und hormonelle Untersuchungen an einem Mann mit Karyotyp 46,XX

The hormone values of FSH, LH, testosterone, 17-beta-oestradiol, prolactin and TSH in the blood serum of a 46,XX male were established. The results obtained are compared with the data of analogical investigations of twelve healthy men and ten men with Klinefelter's syndrome. In the case of XX male syndrome a decreased value of testosterone and elevated values of gonadotropins especially of FSH were established. The levels of oestradiol and TSH were normal. Prolactin was increased, near the middle range of the group with Klinefelter's syndrome.

Pituitary and Testicular Response to LH-RH and to a Long-Acting Analogue (D-Leu-6-LH-RH-Ethylamide)

The LH, FSH and testosterone response to 50 microgram i.v. LH-RH and to 2.5, 5.0, 10.0, and 20.0 microgram i.m. D-Leu-6-LH-RH-ethylamide was studied in 6 subjects with normogonadotrophic, idiopathic oligozoospermia. All injections were given between 8:00 and 9:00 a.m. at weekly intervals. Blood samples were collected before and 30 and 45 minutes after injection of LH-RH, and before and 2, 4, 6, 12, and 24 hours after D-Leu-6-LH-RH-ethylamide injections. Serum levels of LH, FSH, and testosterone were measured by triplicate by R.I.A. LH and FSH responses to LH-RH showed peak values at 30 minutes, whereas following injections of D-Leu-6-LH-RH-ethylamide, maximal values were recorded between 4 and 6 hours and were higher than those obtained with LH-RH. A significant rise of serum testosterone levels was observed after all stimuli, with peak values 45 minutes after LH-RH and 4 to 6 hours after D-Leu-6-Lh-RH-ethylamide injections. The testosterone levels obtained following LH-RH and different doses of the analogue did not differ significantly from one another. The same sequence of maximal LH and FSH values was obtained after injections of LH-RH and of D-Leu-6-LH-RH-ethylamide, particularly at doses of 10.0 and 20.0 microgram. This suggests that the gonadotrophin response to these agents would be a true reflection of the individual mode of pituitary response.

Semen analysis in alcohol dependence syndrome.

Analysis of seminal fluid samples from 20 ADS cases is reported for the first time. A significant decrease in the total volume of complete semen sample and sperm concentration was observed. Percentage of morphologically abnormal sperms was higher in samples from ADS cases than controls, though no linear correlation was observed with amount and duration of alcohol consumption. Analysis of blood samples from five ADS cases, using radio immunoassay techniques showed low testosterone values. LH, FSH and Prolactin values were within normal range. The study shows that alcohol consumption fo a considerable period, affects spermatogenesis, spermiogenesis and causes oligozoospermia. The effect probably are reversible.

Hypogonadism of male prolactinomas: Relation to pulsatile secretion of LH: Hypogonadisms des Mannes mit Prolaktinomen: Beziehungen zur pulsatilen LH-Sekretion

In order to investigate whether a hypothalamic disorder cause hypogonadism in male prolactinomas, LH pulsatile secretion was studied in 13 male patients. Serum PRL levels ranged from 186 to 45,000 ng ml-1 before treatment, and all the tumors were macroadenomas. Reduced LH secretion was revealed in 5 of 13 patients, and FSH was reduced in 1 of 13. Serum testosterone (T) levels were lower than the normal limit in all the patients. HCG tests in 3 patients showed good responses, but the peak values of T were lower than those of normal men. LH pulsatilities were examined in 5 hyperprolactinemic patients before treatment, in 4 hyperprolactinemic patients after operation, and in 8 normoprolactinemic patients after operation and/or bromocriptine treatment. There was no significant difference of the mean LH values, the frequencies of LH pulses, and amplitudes among the hyperprolactinemic patients before operation (n = 5), the normoprolactinemic patients after operation (n = 8), and normal men (n = 7). From these results, it was evident that the hypothalamus and pituitary function of male prolactinomas were well preserved, in spite of higher serum PRL levels and larger tumor size than those reported in females. It is suggested that the main cause of hypogonadism in these patients is due to testicular dysfunction resulting from excessive serum PRL.

Influence of an Aromatase Inhibitor (4-Acetoxy-4-Androstene-3,17-Dione) on Experimentally Induced Impairment of Spermatogenesis in Immature Rats/Einfluß eines Aromatasehemmers (4-Acetoxy-4-Androsten-3,17-dion) auf die experimentell induzierte Hemmung der

Subcutaneous treatment of immature male rats with an estrogen precursor, 19-hydroxy-testosterone (19-OHT), at a daily dose of 1 mg/animal for 14 days leads to a significant decrease in the weight of testis, ventral prostate and seminal vesicle. The peripheral levels of LH are lowered. Testicular histology indicates that the effects of 19-OHT are very similar to the known of effect induced by estradiol-17 beta. 19OHT induces a marked impairment of spermato- and spermiogenesis. The maturation division is completely inhibited. The effect of 19-OHT on spermatogenesis is partially reversed by concomitant administration of an aromatase inhibitor (4-acetoxy-4-androstene-3.17-dione, (4-AA] at a dose of 1 mg/animal/day s.c. Meiotic activity is restored, and the weights of genital organs and the serum LH values increase. 4-AA alone has no appreciable effect on the parameters examined in this study. The present results suggest that specific inhibitors of estrogen biosynthesis might not only be useful to investigate the patho-physiological role of estrogens on spermatogenesis, but also be suitable to some extent for the treatment of estrogen-induced infertility in men suffering from idiopathic oligozoospermia.

Metformin administration was associated with a modification of LH, prolactin and insulin secretion dynamics in women with polycystic ovarian syndrome

Aim. To elucidate the dynamics of FSH, LH, prolactin (PRL), TSH and insulin secretion in women with polycystic ovarian syndrome (PCOS) treated with metformin (MET).Patients and methods. In a prospective, controlled and randomised trial, 32 women with PCOS and 32 with normal cycle were recruited to receive MET (850 mg b.i.d.) or placebo (n: 16 for each subgroup) for an average of 40 days. Pituitary function and insulin secretion were assessed before and after intervention by GnRH-TRH tests and oral glucose tolerance test induced insulin response.Results. Basal and area under the response curve (AURC) LH values were higher in PCOS than in normal controls before MET and declined following treatment in the former group (P < 0.05). Ovulatory PCOS responders had lower basal LH, AURCLH and AURCPRL values during MET than anovulatory cases (P < 0.05 for all) and AURCins was lower in ovulatory than anovulatory PCOS before and on MET (P < 0.02–P < 0.05), with a rise of QUICKY index in the former group during MET treatment (P < 0.05). FSH and TSH were similar.Conclusions. MET administration lowered LH activity in all PCOS women and in ovulatory responders and also compromised PRL stimulated secretion in the latter cases. These findings were indicative of an effect of MET on pituitary activity.

Blood ghrelin, resistin, and adiponectin concentrations during the normal menstrual cycle

To investigate changes of ghrelin, resistin, and adiponectin levels in the circulation during the normal menstrual cycle. Longitudinal study. The study was conducted at a university hospital. Eight healthy normally cycling women. The women were observed during a whole menstrual cycle. Daily blood samples were taken every morning, after overnight fasting, from day 2 of the cycle until the next menstrual period. Plasma acylated and unacylated ghrelin and serum resistin, adiponectin, FSH, LH, E(2), and P levels were measured in all blood samples. In all women serum FSH, LH, E(2), and P levels, normalized to the midcycle peak LH value, showed the typical changes of the normal menstrual cycle. Acylated and unacylated ghrelin, resistin, and adiponectin levels did not change significantly during the whole menstrual cycle. The present study shows for the first time that plasma ghrelin and serum resistin levels do not change significantly during the normal menstrual cycle. It is also confirmed that serum adiponectin levels remain stable throughout the cycle. It is suggested that ovarian steroid dynamics during the cycle have no effect on the secretion of these substances.

A new LH receptor splice mutation responsible for male hypogonadism with subnormal sperm production in the propositus, and infertility with regular cycles in an affected sister

Inactivating LH receptor (LHR) mutations have been described so far in men as well as in women. Phenotypes in men have been variable with in nearly all cases impairment of sex differentiation or azoospermia. We report a milder reproductive phenotype both in a male patient and his sister. We describe a family that carries a homozygous mutation G-->A at position -1 at the intron 10-exon 11 boundary of the LHR gene. The male patient presented with delayed puberty, micropenis and oligospermia. Two of his sisters were homozygous for the same mutation and were infertile. Surprisingly, one of them was found to have had regular ovarian cycles for years and showed normal LH values (6.5 and 10.6 mIU/ml for LH and FSH, respectively). In vitro analysis showed that this altered splicing resulted in an LHR from which eight amino acids are deleted from the extracellular domain (Delta Tyr(317)-Ser(324)). In vitro expression has shown that the receptor was expressed and capable of LH-induced signaling, albeit with reduced potency (P < 0.001). LHR mutations may represent an underestimated cause of infertility in women, in addition to being responsible for male hypogonadism with reduced spermatogenesis.

Oral contraceptive pretreatment in women undergoing controlled ovarian stimulation in ganirelix acetate cycles may, for a subset of patients, be associated with low serum luteinizing hormone levels, reduced ovarian response to gonadotropins, and early pregnancy loss

Oral contraceptive pretreatment facilitated scheduling of pure FSH/GnRH antagonist cycles but in a small subset of patients was associated with low serum LH levels, reduced ovarian response, and early pregnancy loss. Supplementation with LH could be examined as a possible way to improve cycle outcome.

Premature thelarche: clinical and laboratorial assessment by immunochemiluminescent assay

In order to establish cut-off limits and to distinguish isolated premature thelarche (IPT) from precocious puberty (PP), we evaluated data from 79 girls with premature thelarche, comparing basal and stimulated LH and FSH serum concentrations with those from 91 healthy girls. A GnRH stimulation test was performed in 10 normal girls and in 42 with premature thelarche. Comparison among groups was performed by Kruskal-Wallis and Dunns tests. LH values were significantly greater in girls with IPT than in control groups. Basal gonadotropin concentrations were higher in patients with PP than in controls, but not different from patients with IPT. Peak LH levels after GnRH stimulation distinguished those two groups, with a cut-off value of 4.0 IU/L, but still with minimal overlap. In conclusion, a girl with premature thelarche and LH peak value above 4.5 IU/L has, indeed, PP, but values between 3.5 and 4.5 IU/L point to careful follow-up.

LH surge in Nelore cows ( Bos indicus), after induced estrus or after ovarian superestimulation

Considering that there is limited information about the preovulatory LH surge in Zebu cattle ( Bos indicus), the purpose of the present work was to assess the LH surge in Nelore cows during the estrous cycle and after ovarian superestimulation of ovarian follicular development with FSH. This information is particularly important to improve superovulatory protocols associated with fixed-time artificial insemination. Nelore cows ( n = 12) had their estrus synchronized with an intravaginal device containing progesterone (CIDR-B ®) associated with estradiol benzoate administration (EB, 2.5 mg, i.m., Day 0). Eight days later all animals were treated with PGF2α (Day 8) in the morning (8:00 h) and at night, when CIDR devices were removed (20:00 h). Starting 38 h after the first PGF2α injection, blood sampling and ovarian ultrasonography took place every 4 h, during 37 consecutive hours. Frequent handling may have resulted in a stress-induced suppression of LH secretion resulting in only 3 of 12 cows having ovulations at 46.7 ± 4.9 and 72.3 ± 3.8 h, respectively, after removal of CIDR-B. Thirty days later, the same animals received the described hormonal treatment associated with FSH (Folltropin ®, total dose = 200 mg) administered twice a day, during 4 consecutive days, starting on Day 5. Thirty-six hours after the first injection of PGF2α, to minimize stress, only seven blood samples were collected at 4 h interval each, and ultrasonography was performed every 12 h until ovulation. In 11 of 12 cows (92%) the LH surge and ovulation were observed 34.6 ± 1.6 and 59.5 ± 1.9 h, respectively, after removal of progesterone source. The maximum values for LH in those animals were 19.0 ± 2.6 ng/ml (mean ± S.E.M.). It is concluded that, in Nelore cows submitted to a ovarian superstimulation protocol, the LH surge occurs approximately 35 h after removal of intravaginal device containing progesterone, and approximately 12 h before the LH surge observed after an induced estrus without ovarian superstimulation.

OCTOBER 2007 CASE 2: A 61‐YEAR‐OLD MAN WITH HYPONATREMIA

The case of a 61-year-old man presenting with dizziness, nausea, vomiting, reduced serum osmolality, and hyponatremia is reported. Endocrinologically, low levels for ADH, cortisol and testosterone as well as low-normal values for ACTH, LH and FSH were detected. Cranial computed tomography and MRI scans revealed an intra- and suprasellar tumor of adenoma-like appearance with elevation of the optic chiasm. No infiltration of the cavernous sinus was seen. After transsphenoidal resection of the tumor, no additional anterior lobe insufficiencies or diabetes insipidus occurred. Histological examination revealed a tumor consisting of spindle-shaped cells of uniformly high cellularity with no evidence of hypocellular areas. A cellular schwannoma was diagnosed. An intrasellar cellular schwannoma clinically and radiologically mimicking a non-secreting pituitary adenoma is uncommon. However, rare entities like schwannomas, melanocytomas or pituicytomas have to be considered in addition to the more common tumors like pituitary adenomas and meningiomas.

Luteal phase oestradiol suppression by letrozole: a pilot study in oocyte donors

This prospective randomized controlled pilot study was conducted in a tertiary referral university hospital to evaluate whether the administration of letrozole in the luteal phase of stimulated IVF cycles, through a decrease in oestradiol, could alter the suppressed LH levels in the luteal phase. Following oocyte retrieval, six oocyte donors aged ≥ 36 years were randomized to receive either 5 mg letrozole ( n = 3) or placebo ( n = 3). On days 4, 7 and 10 after human chorionic gonadotrophin (HCG) administration, oestradiol levels of the letrozole group were significantly lower compared with the placebo group ( P = 0.008, P = 0.005 and P = 0.004, respectively). LH and progesterone values were comparable between both groups at all time points measured. This study demonstrates that the addition of 5 mg of letrozole in the luteal phase of stimulated donor IVF cycles significantly alters the oestradiol levels on days 4, 7 and 10 after HCG administration for final oocyte maturation. The progesterone and LH profiles of patients treated with letrozole during the same period were not altered compared with the placebo group.

Device Design of High–Speed Source–Heterojunction–MOS Transistors (SHOTs): Optimization of Source Band Offset and Graded Heterojunction

We have studied the device design of 15-nm highspeed n-channel source-heterojunction-MOS transistors (SHOTs) utilizing high-velocity electron injection from the source into the channel region and using the conduction-band-offset energy between the source and the channel regions. The band-offset energy near the source region and the length of the graded heterojunction are key parameters for realizing high-speed operation of SHOTs. A 2D device simulator indicates that the enhancement in transconductance Gm in SHOTs on an SOI substrate over conventional SOI-MOSFETs without source-heterojunction structures strongly depends on the source conduction-band-offset value DeltaEc and the length of graded-heterojunction structures LH in SHOTs. Moreover, the Gm enhancement of SHOTs is affected by the drain and the gate biases. We have shown that, with fully optimized DeltaEc and LH values, the Gm enhancement of SHOT due to high-velocity electron injection can be achieved in a whole range of drain bias. The optimized SHOT is quite promising for high-speed CMOS devices in the 10-nm regime.