摘要:

Cytogenetic and histological studies were carried out on a series of 68 men during investigations for subfertility. Somatic chromosome analysis identified 4 cases with abnormal karyotypes. Meiotic chromosome analysis identified 4 cases with abnormal meiosis. Analysis of cell stages of the spermatogenic cycle in cytogenetic preparations identified 12 cases with missing cell cycle stages. Histological analysis of tissue samples identified defects of the spermatogenic cycle in 23 cases. A kinetic model of spermatogenesis is used in order to relate the different types of abnormality to the spermatogenic cycle.

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00239.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

The suppressive effects of chronic testosterone administration on the rat testicular interstitial cells (Leydig cells) were investigated by stereological methods. The volume of cells, nuclei, mitochondrial compartment and smooth endoplasmic reticulum (SER), as well as the surface area of SER and mitochondrial cristae decreased significantly as a function of the duration of treatment. The decrease in the SER volume accounted for about 75–80% of that in the cell volume. These findings lend support to the view that SER is the subcellular organelle more responsive to the changes in the functional activity of rat Leydig cell

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00240.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

Groups of 6 adult male rats were killed at 4‐h intervals over 24 h periods. The serum samples were assayed for LH, FSH, prolactin (Prl) and testosterone (T). LH, FSH and lactogen receptors were measured in the testis homogenates. In the 2 experiments performed, statistically significant (P<0.01‐0.05) positive correlation was observed between serum LH and T levels, as well as between serum LH and testis LH receptor concentrations. Significant (P<0.05) diurnal variation was seen in peripheral serum T (high levels at 08.00–12.00 h, low levels at 16.00–20.00 h) and LH (high at 24.00–08.00 h. low at 12.00–20.00 h), whereas FSH and Prl levels did not display significant variations over the period of 24 h. The testicular content of LH receptors showed significant (P<0.05) diurnal periodicity in the 2 experiments performed. Maximal binding measured in each experiment was betwee 04.00 and 08.00 h. The low binding was in one experiment between 12.00 and 20.00 h. and in the other between 20.00 and 24.00 h. No consistent variation was measured in testicular FSH or lactogen receptors. These results suggest that, in addition to differential stimulation of steroidogenesis, physiological variations in gonadotrophin levels can induce autoregulatory changes in the testicular gonadotrophi

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00241.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

Testicular androgen production is regulated by circulating LH, the effect of which is mediated by its testicular membrane receptors. In the present study, testicular [125I]hCG binding in man was investigated and found to be characterized by saturability and high affinity (mean KDin testes of 21 patients with prostatic carcinoma = 1.64 times 10‐10M), and stimulated testosterone production in dispersed interstitial cells in vitro. The concentrations of the LH receptors correlated with serum FSH concentrations (r = 0.52,P<0.05) but not with circulating LH levels. Neither had they any correlation with intratesticular testosterone, 5α‐dihydrotestosterone, androstenedione, progesterone, 17‐hydroxyprogesterone or pregnenolone concentrations, which may be due to the fact that LH receptors are confined to Leydig cells, whereas steroids may be unevenly distributed in the different cells of the testis. In contrast, the concentrations of the LH receptor displayed positive correlations with the concentrations of testosterone (r = 0.81,P<0.001), androstenedione (r = 0.54,P<0.05), 17‐hydroxyprogesterone (r = 0.76,P<0.001) and progesterone (r = 0.60,P<0.05) in the spermatic vein serum of the patients. Our data suggest that the Leydig cells mainly responsible for steroid secretion into the blood are under gonadotrophic control exerted via their receptors, whereas Leydig cell function is not rapidly reflected in steroid concentrations within the testi

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00242.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

The effects of [(imBzl)‐D‐His6, Pro9‐NEt]GnRH and [D‐Trp6. Pro9‐NEt]GnRH on testicular function in rats was evaluated. In adult rats the administration of 0.01, 0.1 or 10 μg of either agonist induced rapid increases in serum LH, FSH and testosterone (T) levels which started to decline within several hours. Both agonists caused a decrease in testicular LH and FSH receptor concentrations. The testicular FSH receptor concentration started to decline earlier than the LH receptor concentration but, both reached their lowest levels by day 2 after the administration of the agonists. The recovery of FSH receptor content was slower than that of LH. The extrapituitary effects of the 2 agonists were investigated in immature hypophysectomized animals. Administration of hCG (5 IU daily) to hypophysectomized rats for 5 days caused an increase in serum T levels. Concomitant administration of either of the agonists (10 μg) inhibited the steroidogenic action of hCG. Administration of the agonists alone caused a reduction in testicular LH receptor concentration in hypophysectomized rats. Treatment of the hypophysectomized rats for 0–4 days suggested that the direct antitesticular action of the agonists requires 1 ‐ 2 days to

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00243.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

D‐Tryptophan‐6‐LH‐RH was assessed in the treatment of patients with normogonadotropic oligoasthenozoospermia in 18 subjects selected on the basis of at least 3 spermiograms, long standing infertility, normal LH, FSH, prolactin and testosterone serum levels and lack of evidence of any other pathologic involvement. Testicular biopsies performed on these patients showed hypospermatogenesis with foci of alteration at the spermatid stage in some of them. D‐Trp‐6‐LH‐RH was administered in for 90 days at a dose of 5 μg every 2 days, 10 μg daily or 10 μg every 2 days. There was no significant improvement in the concentration of spermatozoa or in the motility and vitality parameters. Moreover, in 5 patients who received 10 μg daily, basal levels of LH and FSH and the response to LH‐RH, decreased significantly during treatment. D‐Trp‐6‐LH‐RH at the dose used in this study does not seem useful for the treatment of oligoasthenozoosperm

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00244.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

Low sperm counts, low motility indices and a high number of abnormal sperm cells were found in 2/3 of 35 patients who were examined after unilateral orchiectomy for malignant germ cell tumour and before retroperitoneal surgery and/or chemotherapy/radiotherapy. Most of the patients also had slightly reduced serum testosterone levels. Cryopreservation of semen from these patients therefore appears to be of little value in most of the cases.

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00245.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

The effect of hGH therapy on testicular response to hCG was studied in 7 pre‐pubertal boys with known growth hormone deficiency. Each boy received 2000 IU hCG intramuscularly for 3 consecutive days either before starting hGH therapy or 4 months after temporarily discontinuing hGH therapy. A second 3 day series of hCG injections was administered after each boy had received 4 months of hGH treatment. Before each hCG challenge, serum concentrations of testosterone, LH and FSH were obtained and an iv GnRH test was performed. Growth hormone treatment either maintained ***or established linear growth velocities equal to or greater than expected for the patient's skeletal age. Testicular response off hGH therapy, either maximum serum concentration of testosterone or maximum rise above baseline, was not significantly different than testicular response while on hGH therapy. Testicular responses did not correlate significantly with either basal concentration of gonadotrophins or gonadotrophin responses to GnRH. Despite its effectiveness in stimulating growth, hGH did not effect testicular responsiveness to hCG in pre‐pubertal boys with hGH deficie

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00246.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

The effect of mechanically dispersing rat testes prior to collagenase treatment on the activity of the subsequently isolated Leydig cells has been investigated. The latter were obtained by centrifugation of the testes cells on Percoll density gradients. It was found that the lutropin‐stimulated testosterone and cyclic AMP production were 5 and 3 times higher, respectively, in the purified Leydig cells when the mechanical dispersion was omitted, whereas the specific binding of human choriogonadotrophin was unchanged. It is concluded that mechanical treatment of rat testes, unlike mouse testes, decrease the activity of the Leydig cell

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00247.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY

摘要:

The effect of thyroidectomy (Tx) on some key enzymes involved in glycolysis and the HMP‐shunt pathway were studied in the testis of pre‐pubertal, pubertal and adult rats. Hexokinase (HK) and phosphofructokinase (PFK) did not show any significant change in activity after Tx. However, pyruvate kinase (PK) activity was reduced after Txin the testis of pre‐pubertal animals although in pubertal and adult rats it was not affected. Both glucose‐6‐phosphate dehydrogenase (G6P‐DH) and 6‐phosphogluconate dehydrogenase (6‐PG‐DH) activities were reduced after Txand thyroxine (T4) replacement brought both enzyme activities back towards normal. The possible effect of the thyroid on testicular steroidogenesis acting through the HMP

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1982.tb00248.x

出版商:Blackwell Publishing Ltd    

年代:1982

数据来源: WILEY