ABSENCE OF POSITIVE FEEDBACK EFFECT OF OESTROGEN ON LH RELEASE IN PATIENTS WITH TESTICULAR FEMINIZATION SYNDROME

1978 ◽  
Vol 87 (2) ◽  
pp. 259-267 ◽  
Author(s):  
Toshihiro Aono ◽  
Akira Miyake ◽  
Takayuki Kinugasa ◽  
Keiichi Kurachi ◽  
Keishi Matsumoto

ABSTRACT The response of serum LH to exogenous oestrogen administration was studied in 5 patients with testicular feminization syndrome (TFS). The serum LH levels were elevated in all the patients, while serum testosterone levels were within the normal male range. Serum FSH levels were elevated in 4 patients and normal in one patient. Intravenous administration of 100 μg of LH-RH provoked a further increase in both LH and FSH. Following intravenous injection of 20 mg of conjugated oestrogen (Premarin®), the LH levels were serially determined until 120 h in TFS patients, 5 normal males, and 10 normal females during the mid-follocular phase (D7-9). Both TFS patients and normal males showed no LH release following oestrogen injection in contrast to normal females who displayed a significant increase in LH with a peak at 48 to 56 h after the injection. These results seem to suggest that the insensitivity of the hypothalamus to androgen in TFS patients do not affect the sex differentiation of the hypothalamus. The possible role of oestradiol conversion from testosterone in the hypothalamus is discussed.

1985 ◽  
Vol 106 (2) ◽  
pp. 243-248 ◽  
Author(s):  
A. C. Roberts ◽  
M. H. Hastings ◽  
N. D. Martensz ◽  
J. Herbert

ABSTRACT The role of endogenous opiates in the regulation of photoperiodically induced testicular regression was studied in the male Syrian hamster. In reproductively active hamsters exposed to a long photoperiod (LD; 16 h light: 8 h darkness) or to short days (SD; 8 h light: 16 h darkness) for 20 weeks or to SD after pinealectomy, administration of naloxone, a competitive opiate receptor antagonist, at doses of 2·5–20 mg/kg, significantly increased serum LH concentrations. In marked contrast, these doses of naloxone did not produce any change in LH levels in reproductively quiescent hamsters exposed to SD for 8 weeks. The influence of gonadal steroids on the LH response to naloxone was studied in hamsters castrated or castrated and implanted s.c with a capsule containing testosterone. Naloxone did not induce LH release in castrated hamsters maintained in LD or in SD, but this response was restored in LD but not SD when serum testosterone concentrations were maintained at levels similar to those observed in intact reproductively active hamsters. These results show that inhibition of reproduction by the photoperiod prevents naloxone-induced LH release in the male hamster. This lack of response to naloxone is not due, however, to the lower testosterone titres present in these animals compared with reproductively active animals. Responsiveness to naloxone can be restored when the animal is rendered insensitive to the inhibitory photoperiod either by removal of the pineal gland or by induction of photorefractoriness by extended exposure to SD. J. Endocr. (1985) 106, 243–248


1979 ◽  
Vol 91 (1) ◽  
pp. 184-192
Author(s):  
Evangelina Valdés ◽  
Carlos Fernández del Castillo ◽  
Raul Gutiérrez ◽  
Fernando Larrea ◽  
Martha Medina ◽  
...  

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.


1972 ◽  
Vol 70 (2) ◽  
pp. 331-341 ◽  
Author(s):  
Roland R. Tremblay ◽  
Thomas P. Foley ◽  
Pierre Corvol ◽  
In-Joo Park ◽  
Avinoam Kowarski ◽  
...  

ABSTRACT Twenty patients with the syndrome of testicular feminization have been studied along with a group of normal subjects of both sexes and of comparable ages. Peripheral and gonadal venous blood were analysed for their content in testosterone (T), androstenedione (Δ), dihydrotestosterone (DHT), testosterone-oestradiol binding globulin (TeBG), luteinizing hormone (LH) and follicle stimulating hormone (FSH). Normal or even higher than normal male concentrations of T, Δ, and DHT were observed. An actual secretion of the three androgens by the testis was demonstrated. Elevated levels of serum LH were found despite normal male or higher levels of T, Δ, and DHT. High concentrations of TeBG presumably could alter the dynamics of plasma androgens. The gonadal production of DHT and the normal levels of DHT in peripheral plasma shows that 5α-reductase activity is definitely present in the patients.


1986 ◽  
Vol 61 (6) ◽  
pp. 2045-2049 ◽  
Author(s):  
A. N. Elias ◽  
K. Iyer ◽  
M. R. Pandian ◽  
P. Weathersbee ◽  
S. Stone ◽  
...  

The plasma beta-endorphin (beta-EP) and beta-lipotropin (beta-LPH) response to acute exercise and the relationship of these opioid peptides to basal and luteinizing hormone-releasing hormone (LRH)-stimulated luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion was studied in eight normal male volunteers. Acute exercise resulted in a rise in plasma beta-LPH levels that returned to base line when measured 60 min after exercise. Plasma beta-EP levels did not demonstrate any rise when measured immediately after 20 min of exercise or at 60 min after exercise. Serum LH concentrations in individual volunteers declined to nadir values 60–180 min after exercise after which they showed a rebound to levels higher than the preexercise values in three of five volunteers in whom nadir LH levels were attained before the final (180 min) measurement. Serum FSH concentrations were unaltered by exercise. Acute exercise similarly did not alter the LH/FSH response to exogenous LRH stimulation. Pretreatment of the volunteers with the narcotic antagonist, naloxone, failed to alter the postexercise or LRH-stimulated LH and FSH release. The data suggest that beta-EP does not exert a suppressive effect on LH secretion after acute exercise in normal human males. Whether the suppression of LH secretion after acute exercise in unconditioned males is due to factor(s) cosecreted with beta-LPH, an increase in brain beta-EP or to alternate mechanisms such as alteration in central dopaminergic or GABAergic tone remains to be established.


1979 ◽  
Vol 91 (3) ◽  
pp. 591-600 ◽  
Author(s):  
Toshihiro Aono ◽  
Akira Miyake ◽  
Takenori Shioji Motoi Yasuda ◽  
Koji Koike ◽  
Keiichi Kurachi

ABSTRACT Five mg of bromocriptine was administered for 3 weeks to 8 hyperprolactinaemic women with galactorrhoea-amernorrhoea, in whom the response of serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) to 100 μg of iv LH-releasing hormone (LH-RH) had been evaluated. Twenty mg of conjugated oestrogen (Premarin®) was injected iv any day between the 10th and 12th day from the initiation of the treatment, and serum LH levels were serially determined for 120 h. Hyperresponse of LH with normal FSH response to LH-RH was observed in most patients. Bromocriptine treatment for 10 to 12 days significantly suppressed mean (± se) serum prolactin (PRL) levels from 65.1 ± 23.0 to 10.4 ± 2.0 ng/ml, while LH (12.6 ± 2.1 to 24.8 ± 5.9 mIU/ml) and oestradiol (40.1 ± 7.6 to 111.4 ± 20.8 pg/ml) levels increased significantly. Patients on bromocriptine treatment showed LH release with a peak at 48 h after the injection of Premarin. The mean per cent increases in LH were significantly higher than those in untreated patients with galactorrhoea-amenorrhoea between 32 and 96 h after the injection. The present results seem to suggest that the restoration of LH-releasing response to oestrogen following suppression of PRL by bromocriptine may play an important role in induction of ovulation in hyperprolactinaemic patients with galactorrhoea-amenorrhoea.


1978 ◽  
Vol 76 (3) ◽  
pp. 417-425 ◽  
Author(s):  
C. A. BLAKE ◽  
PATRICIA K. BLAKE ◽  
NANCY K. THORNEYCROFT ◽  
I. H. THORNEYCROFT

The effects of coitus and injection of luteinizing hormone releasing hormone (LH-RH) on serum concentrations of LH, testosterone and dihydrotestosterone (17β-hydroxy-5α-androstan-3-one; DHT) were tested in male rabbits. Before experimentation, male and female rabbits were housed in individual cages in the same room. Male rabbits were then bled by cardiac puncture before and after placement with female rabbits or intravenous injection of LH-RH. Serum LH, testosterone and DHT were measured by radioimmunoassay. Sexual excitement (sniffing, chasing and mounting), with or without intromission, caused a marked rise in serum testosterone and DHT concentrations in only some of the bucks. These increases were accompanied or preceded by a small, transient increase in serum LH. In the rest of the bucks, sexual excitement with or without intromission had either no effect on serum levels of all three hormones, or only serum testosterone and DHT decreased during the collection period. Similar responses were measured in bucks which were housed in a room without does for 2–4 weeks before experimentation. Injection of 10, 30 or 100 ng or 50 μg LH-RH caused serum LH, testosterone and DHT to rise in all bucks tested, but the magnitude of the rises in serum testosterone and DHT were not related to the magnitude of the LH rise. In both mated and LH-RH-injected bucks, the rises in serum testosterone and DHT were greatest in animals with low initial testosterone and DHT values. Under the conditions of this study, the data suggest that: (1) serum testosterone and DHT rise in only some male rabbits after sexual excitement (with or without intromission), (2) the rises in serum testosterone and DHT are dependent on a small transient increase in serum LH and (3) sexual excitement is less likely to cause release of LH-RH in bucks with raised serum testosterone and DHT concentrations.


1980 ◽  
Vol 95 (3) ◽  
pp. 314-318 ◽  
Author(s):  
Martha Medina ◽  
Alfredo Ulloa-Aguirre ◽  
Maria A. Fernández ◽  
Gregorio Pérez-palacios

Abstract. The role of oestrogens on gonadotrophin secretion was assessed in three related patients with the complete form of testicular feminization syndrome. Serum LH and FSH levels were measured before and after I.RH stimulation as well as before, during and after chronic clomiphene citrate administration. Moderately elevated LH basal levels with a significant LH rise following I.RH were observed. Normal or even low FSH level with poor response to LRH were found in all subjects. Administration of clomiphene citrate resulted in a significant serum LH increase without any change of FSH. Following castration both LH and FSH rose and a normal response to LRH was observed. These results were interpreted as demonstrating that, while endogenous oestrogens modulate LH secretion in patients with androgen unresponsiveness, it plays no role in regulating FSH secretion and suggested that a factor of testicular origin without androgenic or oestrogenic activity is responsible for FSH regulation.


1993 ◽  
Vol 139 (2) ◽  
pp. 253-258 ◽  
Author(s):  
A. M. Salicioni ◽  
R. W. Carón ◽  
R. P. Deis

ABSTRACT There is evidence that the adrenals play a role in the regulation of the synthesis and release of gonadotrophins in various vertebrates. The aim of this study was to determine the part played by adrenal steroids, with special reference to progesterone, on the concentration of LH in ovariectomized (OVX) and oestrogen-primed rats. OVX rats received a single s.c. injection of vehicle or oestradiol benzoate (OB, 20 μg/rat). This day was designated as day 0. Three or four days later (day 3–day 4), the rats were treated with mifepristone (10 mg/kg) or with two doses of progesterone antiserum and blood samples were obtained at 13.00 and 18.00 h. OB treatment of OVX rats reduced serum LH at 13.00 h and 18.00 h on day 3 but only at 13.00 h on day 4. The administration of mifepristone at 08.00 h to OVX and oestrogen-treated rats induced a significant increase in serum LH at 18.00 h on days 3 and 4, without modifying the values at 13.00 h. When mifepristone was given at 13.00 h a much larger increase in serum LH was obtained at 18.00 h. In OVX and oestrogen-treated rats, adrenalectomy on day 2 (08.00–09.00 h) induced an increase in serum LH at 18.00 h similar to that observed in the OVX and oestrogen-primed rats after mifepristone treatment. In order to determine the specificity of the effect of mifepristone, a group of OVX and oestrogentreated rats was injected with progesterone antiserum at 08.00 and 13.00 h on day 3. Serum LH concentrations at 13.00 and 18.00 h on day 3 were similar to values obtained in OVX rats treated with oestrogen and mifepristone. Serum progesterone was measured at 08.00 and 13.00 h in OVX and OVX and oestrogenprimed rats. At both times, values were similar in OVX rats but oestrogen treatment significantly increased serum progesterone levels. The important role of adrenal progesterone on the regulation of LH secretion in OVX and oestrogen-primed rats is evident from these results. Blocking progesterone action at the receptor level, we showed that OB significantly increased LH values at 18.00 h. On the basis of these studies it is tempting to speculate on the possibility of an inhibitory or stimulatory effect of oestrogen on serum LH concentration in OVX rats, according to the presence or absence of adrenal progesterone action. Journal of Endocrinology (1993) 139, 253–258


1977 ◽  
Vol 84 (2) ◽  
pp. 382-389 ◽  
Author(s):  
Ryoyu Takeda ◽  
Misao Ueda

ABSTRACT Variations in serum levels of LH and FSH after administration of synthetic LH-RH, and basal levels of serum testosterone were studied in 9 male patients with myotonic dystrophy. The degree of testicular damage, as determined histologically on biopsy specimens, was also studied. Results were as follows: 1) it was observed that both the basal and stimulated (maximal) levels of serum LH and FSH were significantly higher than levels found in 9 sex- and age-matched normal controls. 2) The basal level of serum testosterone was consistently lower in the patient group. One patient, however, showed a low normal level, which represented a statistically significant reciprocal relation to both LH and FSH levels as expressed on a logarithmic scale. 3) There was a significant trend which indicated that the higher the serum LH, FSH levels, or the lower the basal levels of serum testosterone, the more extensive was the damage to the seminiferous tubules. From these findings it was concluded that hypogonadism in patients with myotonic dystrophy, is characterized by the development of lesions in the seminiferous tubules.


1983 ◽  
Vol 99 (3) ◽  
pp. 355-NP ◽  
Author(s):  
F. Sasaki ◽  
M. Sano

To study the effect of the ovary on sexual differentiation of somatotrophs and lactotrophs, the anterior pituitary glands of castrated adult male mice which had received an ovarian transplant during postnatal development were studied using a stereological morphometric technique with an electron microscope. In adult male mice which were castrated neonatally and given ovarian transplants at the age of puberty (NCT-males), the ovaries contained follicles and corpora lutea. The percentages (∼40) and numbers (∼2 × 105) of lactotrophs were similar in normal dioestrous females and NCT-males, but were higher than the percentage (9·3) and number (4·6 × 104) in normal males. Ovarian grafts in adult male mice which were simultaneously castrated and given an ovarian transplant just before puberty (PCT-males) contained numerous follicles of various sizes but no corpora lutea. The percentage (46·8) and number (3·9 × 105) of lactotrophs were greater in these mice than in dioestrous females. The percentage of somatotrophs in NCT-males (34·7) was less than in normal males (52·6), but was similar to that in dioestrous female mice (37·4). The percentage of somatotrophs in PCT-males (27·4) was less than in normal male and dioestrous female mice. These data indicate that lactotrophs and somatotrophs differentiate to the female phenotype when a cyclically functional ovary is present after puberty.


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