The effects of pulsatile GnRH infusion upon the diurnal variations in serum LH and testosterone in pre-pubertal and pubertal boys

1989 ◽  
Vol 121 (2) ◽  
pp. 241-245 ◽  
Author(s):  
Derek Gordon ◽  
Christina E. Gray ◽  
Graham H. Beastall ◽  
John A. Thomson
Keyword(s):  
Serum Testosterone ◽  
Diurnal Variations ◽  
Early Puberty ◽  
Testosterone Secretion ◽  
Pulsatile Gnrh ◽  
Serum Lh ◽  
Median Serum ◽  
Pubertal Boys ◽  
Pre Treatment ◽  
Gnrh Infusion

Abstract. The aim of the present study was to determine the effects of exogenous GnRH pulsatile infusions on the diurnal variations of LH and testosterone secretion which occur in late pre-puberty and early puberty. GnRH infusions were administered to 12 short stature males in pre-puberty or early puberty, over 6-day periods. In 6 patients, GnRH doses of 2.5, 7.5 and 15 μg/pulse were used and 24-h profiles of serum LH and testosterone were measured before and at the end of the infusions. In the remaining 6 patients GnRH was administered at a dose of 7.5 μg/pulse and profiles between 21.00 and 06.00 h the following day were determined. Pre-infusion profiles demonstrated nocturnal LH and testosterone rises in all patients. Median pre-infusion serum LH prior to midnight was 2.2 U/l (range 1.0–5.4) rising to 3.7 U/l (range 1.9–10.7) during GnRH administration (p < 0.005). After midnight, median pre-treatment serum LH concentration was 4.3 U/l (range 2.7–7.5) which remained unaltered by GnRH administration (median 4.8 U/l, range 2.9–7.9, p > 0.05). Median pre-therapy serum testosterone before midnight was 0.8 nmol/l (range 0.1−7.1) rising significantly (p < 0.05) to 4.1 nmol/l (range 0.2–8.0). Following therapy, post-midnight median serum testosterone rose from 4.8 (range 0.4–9.4) to 7.0 nmol/l (range 0.5–13.9, p > 0.05). Diurnal variation in LH and testosterone secretion, therefore, is maintained during exogenous GnRH administration to pre-pubertal and pubertal boys. Response to exogenous GnRH pulses may be significantly influenced by endogenous GnRH.

Non-responsiveness of serum gonadotropins and testosterone to pulsatile GnRH in hemochromatosis suggesting a pituitary defect

1993 ◽  
Vol 128 (4) ◽  
pp. 351-354 ◽  
Author(s):  
Lise Duranteau ◽  
Philippe Chanson ◽  
Joelle Blumberg-Tick ◽  
Guy Thomas ◽  
Sylvie Brailly ◽  
...  
Keyword(s):  
Single Pulse ◽  
Serum Testosterone ◽  
Pulse Amplitude ◽  
Pulse Frequency ◽  
Gonadotropin Secretion ◽  
Pulsatile Gnrh ◽  
Serum Lh ◽  
Before And After ◽  
Gnrh Therapy ◽  
Lh Secretion

We investigated the potential pituitary origin of gonadal insufficiency in hemochromatosis. Gonadotropin secretion was studied in seven patients with hemochromatosis and hypogonadism, before and after chronic pulsatile GnRH therapy. Pulsatile LH secretion was studied before (sampling every 10 min for 6 h) and after 15-30 days of chronic pulsatile GnRH therapy (10-12 μg per pulse). Prior to GnRH therapy, all the patients had low serum testosterone, FSH and LH levels. LH secretion was non-pulsatile in four patients, while a single pulse was detected in the remaining three. Chronic pulsatile GnRH administration did not increase serum testosterone levels; similarly, serum LH levels remained low: neither pulse frequency nor pulse amplitude was modified. We conclude that hypogonadism in hemochromatosis is due to pituitary lesions.

The contribution of corticosterone and testosterone to the suppression of serum LH in hyperprolactinaemic adult male rats with pituitary transplants

1987 ◽  
Vol 113 (1) ◽  
pp. 111-116 ◽  
Author(s):  
R. F. A. Weber ◽  
M. P. Ooms ◽  
J. T. M. Vreeburg
Keyword(s):  
Adult Male ◽  
Serum Testosterone ◽  
Serum Levels ◽  
Male Rats ◽  
Male Rat ◽  
Serum Concentrations ◽  
Testosterone Secretion ◽  
Accessory Sex Glands ◽  
Serum Lh ◽  
Stimulation Of

ABSTRACT The effects of hyperprolactinaemia on serum levels of LH were investigated in adult male rats of the R × U strain. Hyperprolactinaemia was induced by three pituitary grafts under the kidney capsule, transplanted on day 0 of each experiment. Special attention was paid to the contribution of prolactin-stimulated testes, adrenals and corticosterone. In experiment 1, hyperprolactinaemia significantly reduced the serum concentrations of LH in intact rats. In spite of a significant increase in the serum levels of corticosterone, serum testosterone was not significantly affected by hyperprolactinaemia. The weights of both the adrenals and accessory sex glands were significantly increased at autopsy. In experiment 2, treatment with 10 mg corticosterone s.c. daily from day 14 to day 28 after pituitary grafting significantly reduced serum levels of both LH and testosterone. The suppression of testosterone in the hyperprolactinaemic corticosterone-treated animals was significantly less than in the corticosterone-treated control animals. The weights of the accessory sex glands were significantly increased in the hyperprolactinaemic animals. In experiment 3, rats were adrenalectomized and half of them were substituted with corticosterone. Serum testosterone levels significantly increased in both hyperprolactinaemic adrenalectomized rats and in adrenalectomized corticosterone-treated animals without any significant effect on serum LH. Again the weights of the accessory sex glands were significantly increased in the hyperprolactinaemic animals. In experiment 4, rats were adrenalectomized, gonadectomized and corticosterone treated on day 0 and then implanted with a 2, 1·5 or 1 cm silicone elastomer capsule containing testosterone. On day 28 after pituitary grafting, LH levels were significantly suppressed in animals with a 2 or 1·5 cm testosterone implant. The weights of the accessory sex glands were not increased in the hyperprolactinaemic animals. These results show that in the male rat the inhibitory effects of hyperprolactinaemia on serum LH levels may be due to (1) increased sensitivity of the hypothalamic-pituitary axis to the negative feedback action of testosterone by prolactin and by the prolactin-stimulated corticosterone secretion and (2) stimulation of testicular testosterone secretion by prolactin, which can also explain the increased weights of the accessory sex glands. Even in the presence of high serum concentrations of corticosterone, stimulation of testicular testosterone secretion by prolactin was observed. J. Endocr. (1987) 113,111–116

Pituitary and gonadal function in prepubertal and pubertal cryptorchidism

1980 ◽  
Vol 95 (4) ◽  
pp. 553-559 ◽  
Author(s):  
A. Okuyama ◽  
H. Itatani ◽  
S. Mizutani ◽  
T. Sonoda ◽  
T. Aono ◽  
...  
Keyword(s):  
Serum Testosterone ◽  
Serum Levels ◽  
Seminiferous Tubules ◽  
Gonadal Function ◽  
Testosterone Levels ◽  
Serum Lh ◽  
Bilateral Cryptorchidism ◽  
Pubertal Boys ◽  
The Difference ◽  
Group Serum

Abstract. LRH and hCG tests were performed in 35 prepubertal and 35 pubertal boys with unilateral or bilateral cryptorchidism to examine the pituitary and gonadal function. Twenty-one normal boys were also examined as controls. In the prepubertal group, distinct increases in serum LH, FSH and testosterone levels by LRH and hCG tests were found in all of the normal and unilateral cryptorchid boys. However, no or very little response was observed in 4 out of 17 boys with bilateral cryptorchidism. In the pubertal group, serum levels of LH, FSH and testosterone in normal boys, in unilateral and in bilateral cryptorchid boys were evidently higher than those in the prepubertal group, and distinct or moderate responses by the LRH and hCG tests were found in all boys examined. Although serum testosterone levels were similar in all groups, serum basal and peak gonadotrophin levels by the LRH test were significantly higher in bilateral cryptorchid boys than in normal and unilateral cryptorchid boys. The difference was more marked in FSH than in LH level. An elevated level of serum LH is suggestive of the hypofunction of not only the seminiferous tubules but also of the Leydig cells in cryptorchid testes.

Aging alters feed-forward and feedback linkages between LH and testosterone in healthy men

1997 ◽  
Vol 273 (4) ◽  
pp. R1407-R1413 ◽  
Author(s):  
Thomas Mulligan ◽  
Ali Iranmanesh ◽  
Michael L. Johnson ◽  
Martin Straume ◽  
Johannes D. Veldhuis
Keyword(s):  
Feedback Inhibition ◽  
Serum Testosterone ◽  
Older Men ◽  
Older Individuals ◽  
Deconvolution Analysis ◽  
Feed Forward ◽  
Testosterone Secretion ◽  
Serum Lh ◽  
Lh Secretion ◽  
Secretion Rates

To discern the effect of aging on coordinate luteinizing hormone (LH) and testosterone secretion, we sampled healthy older men (age 62–74 yr, n = 11) and young controls (age 21–34 yr, n = 13) every 2.5 min overnight. Deconvolution analysis and cross-correlation were used to relate serum LH concentrations to calculated testosterone secretion rates (feed-forward stimulation), as well as serum testosterone concentrations to computed LH secretion rates (feedback inhibition). Despite statistically similar mean serum LH and testosterone concentrations in the young and older men, older individuals had diminished feed-forward stimulation of LH concentrations on calculated testosterone secretion rates, as well as delayed feedback inhibition of testosterone concentrations on computed LH secretion rates.

EFFECTS OF GENERAL ANAESTHESIA AND SEVERITY OF SURGICAL STRESS ON SERUM LH AND TESTOSTERONE IN MALES

1975 ◽  
Vol 78 (2) ◽  
pp. 258-269 ◽  
Author(s):  
A. Nakashima ◽  
K. Koshiyama ◽  
T. Uozumi ◽  
Y. Monden ◽  
Y. Hamanaka ◽  
...  
Keyword(s):  
General Anaesthesia ◽  
Surgical Stress ◽  
Fiberoptic Bronchoscopy ◽  
Serum Testosterone ◽  
Major Surgery ◽  
Succinylcholine Chloride ◽  
Serum Luteinizing Hormone ◽  
Serum Lh ◽  
Rate Of Increase ◽  
Male Patients

ABSTRACT Significantly decreased levels of serum testosterone from the pre-anaesthesia level were found during and up to 7 days following major surgery under general anaesthesia (nitrous oxide, oxygen and halothane following induction with thiopental and succinylcholine chloride) in 18 male patients. On the other hand, in the same patients, the serum luteinizing hormone (LH) increased significantly from the pre-anaesthesia level 30 min and 1 h after the beginning of anaesthesia. A slight increase in LH level was also noted on the 7th post-operative day. The determinations of serum testosterone and LH in fiberoptic bronchoscopy under the same general anaesthesia as that used in surgery or local anaesthesia in 26 male patients, revealed that the change in the serum LH during and following surgery seemed to be mainly induced by the general anaesthesia and that the rate of decrease in the serum testosterone may be related to the severity of surgical stress including the anaesthesia. The rate of increase in serum testosterone following the injection of gonadotrophin in 20 males on the 6th post-operative day was similar to that in 10 pre-operative males. The effects of pulmonary lobectomy on serum testosterone and urinary steroids were also studied in 6 males under adrenal suppression with dexamethasone. On the 6th post-operative day, the urinary aetiocholanolone plus androsterone and serum testosterone were found to be half the level of those on the pre-operative day, while the urinary 5β-pregnane-3α,17α,20α-triol remained unchanged. These observations in human are not inconsistent with the report of Tcholakian & Eik-Nes (1971) in dogs namely that a shift in androgen biosynthetic pathway is present in the testis under surgical stress.

ENDOCRINE STUDIES AND SUCCESSFUL TREATMENT IN A PATIENT WITH TRUE HERMAPHRODITISM

1979 ◽  
Vol 91 (1) ◽  
pp. 184-192
Author(s):  
Evangelina Valdés ◽  
Carlos Fernández del Castillo ◽  
Raul Gutiérrez ◽  
Fernando Larrea ◽  
Martha Medina ◽  
...  
Keyword(s):  
Chromosome Complement ◽  
Reproductive Function ◽  
External Genitalia ◽  
Serum Testosterone ◽  
Serum Levels ◽  
Normal Children ◽  
Serum Lh ◽  
Genital Ambiguity ◽  
And Gender ◽  
Lh Rh

ABSTRACT A 12-year old, 46 XX true hermaphrodite born with genital ambiguity was studied and successfully treated. The serum LH and FSH profile resembled that of a pubertal normal individual, and LH-RH administration induced a normal LH response. Baseline testosterone serum levels were within the range for normal children. Exogenous HCG stimulation induced a significant serum testosterone increase up to values similar to those observed in normal post-pubertal males. Surgical examination disclosed the presence of bilateral ovotestis, normal Mullerian derivatives, epididymis, and vas deferens. A complete ovotestis with testicular predominance and the testicular portion of the contralateral ovotestis as well as the Wolffian derivatives, were removed. A further HCG stimulation 3 months after surgery, failed to induce serum testosterone increase. Spontaneous menarche was observed 6 months after surgery and ovulation was well documented. At present the patient has several characteristics of female sex including those of chromosome complement, gonad, internal and external genitalia, hormone levels and gender identity, thus demonstrating that treatment was successful and that reproductive function could be obtained. The finding of spontaneous ovulation following removal of the testicular portion suggests normal cyclic gonadotrophic release implying a difference between animal models and man in regard to hypothalamic virilization.

Increases in testosterone secretion in adult rams with immunoneutralization of endogenous estradiol occur in the absence of increases in pulsatile LH release or testicular LH receptors

1989 ◽  
Vol 120 (2) ◽  
pp. 180-186 ◽  
Author(s):  
Lee M. Sanford
Keyword(s):  
Binding Sites ◽  
Cell Function ◽  
Passive Immunization ◽  
Serum Testosterone ◽  
Experimental Period ◽  
Pulse Amplitude ◽  
Testicular Biopsy ◽  
Binding Activity ◽  
Testosterone Secretion ◽  
Lh Release

Abstract. The testes of the ram become more responsive to LH stimulation following immunoneutralization of endogenous estradiol. The possibility that testosterone secretion is facilitated by increased LH-binding activity in the testes was investigated in the present study conducted with adult Dorset × Leicester × Suffolk rams during the time of testicular recrudescence. Patterns of episodic LH release and testosterone secretion (days –5, 10 and 24) and LH-binding activity in testicular biopsy samples (days –1, 14 and 28) were assessed on the days indicated relative to the onset of passive immunization and the establishment of relatively low titres (~1:200) of estradiol antiserum. During the experimental period, mean serum testosterone concentration increased by approximately 150% for the immunized rams as basal concentration and pulse amplitude increased, while all characteristics of testosterone secretion remained unchanged for the nonimmunized rams. Characteristics of LH release and the concentration of LH-binding sites in the testes, however, were always similar for both groups of rams. Further, group differences in FSH and PRL secretion and in the concentration of testicular FSH-binding sites did not occur. These results provide evidence for an estradiol direct (gonadotropin independent) negativefeedback component in the regulation of Leydig cell function in the ram.

EFFECT OF LONG-TERM INFUSION OF AN LH-RELEASING HORMONE AGONIST ON TESTICULAR FUNCTION IN BULLS

1986 ◽  
Vol 109 (2) ◽  
pp. R9-R11 ◽  
Author(s):  
W. v. Rechenberg ◽  
J. Sandow ◽  
P. Klatt
Keyword(s):  
Treatment Period ◽  
Serum Testosterone ◽  
Constant Infusion ◽  
Continuous Administration ◽  
Entire Treatment Period ◽  
Releasing Hormone ◽  
Testosterone Secretion ◽  
Lhrh Agonists ◽  
Lh Releasing Hormone

ABSTRACT Continuous administration of LH-releasing hormone (LHRH) agonists is an effective method of suppressing testosterone secretion in the male. The effect of the LH-releasing hormone (LHRH) agonist, buserelin, administered to bulls by constant infusion from osmotic minipumps was studied. In one experiment with four treated and one control bull, 109 pg buserelin/day were administered for 22 days. Immediately after implantation, serum testosterone concentrations rose from below 35 nmol/l to 35-105 nmol/l, and all four buserelin-infused bulls showed increased testosterone secretion during the treatment period. After removal of the minipumps, testosterone concentrations decreased to pretreatment levels. In a second experiment bulls were infused for 42 days (four treated and one control), and identical results were obtained. Testosterone secretion was stimulated (52-87 nmol/l serum) during the entire treatment period. These results demonstrate that conditions for stimulation of the pituitary-testicular axis may vary between species. Infusion of low doses of LHRH-agonists in bulls has an extended stimulatory effect without immediate desensitization of gonadotrophin release.

Assessment of Serum Irisin in Overweight And Obese Patient with Polycystic Ovary Syndrome

2020 ◽  
Vol 23 (2) ◽  
pp. 25-34
Author(s):  
Sipel Younis Mustafa ◽  
Shereen. A. Ibrahim
Keyword(s):  
Polycystic Ovary Syndrome ◽  
Obese Patient ◽  
Study Design ◽  
Polycystic Ovary ◽  
Density Lipoprotein ◽  
Lipoprotein Cholesterol ◽  
Control Group ◽  
Ovary Syndrome ◽  
Serum Lh ◽  
Median Serum

Background and Objective: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting 10–15 % of women in reproductive age. The objective was to evaluate the effect of irisin in the etiology of obese patient with PCOS. Study Design and Methods: The study design its a case control study. This study involved fifty obese ladies (50) with confirmed diagnosis of PCOS. The second group served as control group and included forty apparently normal (non-polycystic ovary) obese ladies (40). The following main parameters were measured: Fasting serum levels of total Cholesterol, triglyceride, high density lipoprotein-cholesterol, low density lipoprotein– cholesterol, glycohaemoglobin (HbA1c%), Insulin , Testosterone, FSH, serum LH and Irisin. Results: The median serum Irisin was significantly higher among PCOS cases (119.1 ng/ml) compared to healthy controls (74.7 ng/ml). The median serum FSH was significantly higher among PCOS cases (6.52 ng/ml ) compared to controls (4.72 ng/ml). Serum LH was obviously higher among PCOS cases (6.88 ng/ml) compared to controls (6.08 ng/ml). The mean pulse rate, blood WBC count and serum VLDL were significantly higher (71.6/min, 8.3 mg/dl and 22.5 mg/dl respectively) in cases with PCOS compared to controls (67.5/min, 7.2 mg/dl and 18.5 mg/dl respectively). Conversely, the serum HDL was significantly lower among PCOS cases (43.8 mg/dl) compared to controls (48.4 mg/dl), serum testosterone showed statistically non-significant differences. Conclusion: Data of the present study showed that serum Irisin was significantly higher among PCOS cases. These findings suggest important role of irisin as a biomarker for PCOS and an important factor in the development of PCOS.

Hypergonadotropism in Peripubertal Boys with Chronic Renal Failure

PEDIATRICS ◽  
1983 ◽  
Vol 72 (3) ◽  
pp. 384-389
Author(s):  
Harold K. Marder ◽  
Laxmi S. Srivastava ◽  
Stephen Burstein
Keyword(s):  
Renal Failure ◽  
Chronic Renal Failure ◽  
Elevated Serum ◽  
Serum Testosterone ◽  
Normal Serum ◽  
Adult Men ◽  
Testicular Dysfunction ◽  
Serum Luteinizing Hormone ◽  
Serum Lh ◽  
Serum Gonadotropin

Serum gonadotropin and testosterone concentrations were measured in ten peripubertal boys to assess the effects of uremia on pubertal maturation. Serum luteinizing hormone (LH) concentrations were elevated for stage of puberty in eight boys, whereas in most boys serum follicle-stimulating hormone and testosterone concentrations were normal. Serum LH concentrations correlated with the severity of uremia. LH levels declined when measured 1 year after the initial measurements in four boys who received renal allografts, but were further elevated in two boys who were treated conservatively. Elevated serum LH concentrations in the presence of normal serum testosterone concentrations imply limited testicular sensitivity to the effects of LH in these peripubertal boys, as has been documented for adult men with chronic renal failure. Alternatively, there may be accumulation of an immunoreactive LH molecule that lacks bioactivity. A testicular dysfunction may explain the pubertal delay experienced by some uremic adolescent boys.

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