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1.
A technique for rapidly collecting blood of testicular origin is described, one which can provide sufficient plasma amounts to investigate some steps of testicular steroid biogenesis in vivo in 2 species. In adult male rats, testosterone (T), androstenedione (4A) and 5-androstenediol (5AD) were determined in pampiniform plexus testicular venous blood (PPTV) and peripheral (PV) blood samples before and 2 h after human Chorionic Gonadotropin (hCG). PPTV concentration of 5AD was 0.83 +/- 0.1 ng/ml (mean +/- SEM) with a PPTV/PV ratio of 7.0 +/- 1.0, comparable to a PPTV/PV ratio for 4A of 5.8 +/- 1.8. After hCG, PPTV concentration of 5AD significantly increased to 1.28 +/- 0.15 ng/ml (P less than 0.05). Those data are in favor of a participation of 5-ene pathway to testicular biogenesis of T associated to a 4-ene pathway which is predominant. In adult male Macaca fascicularis, spermatic vein (SV) concentrations of 5AD and 4A were comparable (3.0 +/- 1.2 vs 4.3 +/- 1.0 ng/ml) as well as SV/PV ratios under basal conditions (3.5 +/- 0.9 vs 5.1 +/- 0.1), as well as 48 h after hCG, confirming in vivo that both 5-ene and 4-ene pathways are involved in testicular T biogenesis. Testicular production of estradiol (E2), estrone (E1) and their sulfates E2S and E1S showed a SV/PV ratio significantly higher than 1 (3.4 +/- 0.6; 2.4 +/- 0.1; 1.7 +/- 0.2 and 1.6 +/- 0.2, respectively).  相似文献   

2.
Blood flow to the testis, haemoglobin oxygen saturation and testosterone concentration in arterial and venous testicular blood vessels were studied in Texel rams in the breeding and non-breeding season. Blood flow in the proximal and distal testicular artery was measured electromagnetically. The mean flow in the proximal testicular artery was 18.5 ml/min and in the distal testicular artery 7.5 ml/min, and there was no detectable seasonal influence. Haemoglobin oxygen saturation and testosterone concentration were measured in the saphenous artery and vein, the distal testicular artery and vein, and in the proximal testicular vein. The haemoglobin oxygen saturation in the proximal testicular vein was significantly higher than in the distal testicular vein in both seasons. The mean testosterone concentration was significantly lower in the proximal testicular vein than in the distal testicular vein in both seasons. Based on haemoglobin oxygen saturation and testosterone data, it was calculated that between 28 and 46% of the testicular arterial blood was bypassing the testis and was directly flowing through arterio-venous anastomoses towards the pampiniform plexus in the spermatic cord of conscious rams. In anaesthetized rams 55 and 64% of the blood was flowing directly from the testicular artery to the pampiniform plexus based on blood flow data. Transfer of testosterone and oxygen by passive diffusion from the testicular artery to the pampiniform plexus and vice versa in the spermatic cord was not detected.  相似文献   

3.
Progesterone (P), 17-OH-progesterone (17-OH-P), Androstenedione (delta 4) and testosterone (T) plasma levels were measured in spermatic venous blood of twenty-nine varicocele patients (V) and in twelve normal subjects (N). Our data reveal a significant decrease of the mean testosterone in the spermatic blood of varicocele patients with respect to normal controls: (N = 1708.7 +/- 223.8 (SEM) nmol/l, n = 10. V = 1190.9 +/- 101.1 (SEM) nmol/l, n = 29. P less than 0.03). An inverse correlation has been observed between the age of varicocele patients and 17-OH-P (n = 29. y = -33.38x + 1384.70, r = -0.59, P less than 0.01) and delta 4 values (n = 23, y = -1.62x + 85.65, r = -0.49, P less than 0.05). The 17-OH-P/delta 4 ratio appears significantly augmented in varicocele patients with respect to normal controls (n = 4.80 +/- 0.86 (SEM), n = 12. V = 9.65 +/- 1.21 (SEM), n = 23.0.02 greater than P greater than 0.01). This indicates a deficiency in varicocele patients of 17-20 lyase activity. The positive correlation between the P/17-OH-P ratio and age of varicocele patients (n = 28, y = 0.007 x -0.090, r = 0.45, P less than 0.03) suggests a progressive impairment of 17-alpha-hydroxylase in such patients as they grow relatively older. These data demonstrated that the reduced spermatic levels of testosterone in varicoceles are due to the enzymatic impairment of testosterone biosynthesis, concerning firstly 17-20 lyase activity and secondly 17-alpha-hydroxylase activity. The latter enzymatic impairment is age related as is seen from the significant increase of the P/17-OH-P ratio in older patients.  相似文献   

4.
The mechanism of testosterone (T) production defect in uremic rats has not yet been clearly defined and hypothalamo-hypophyseal impairment as well as primary testicular dysfunction have been suggested. In 42 rats followed monthly after subtotal nephrectomy up to 7.1 +/- 0.3 months, we observed a progressive significant decline of T and androstenedione (A) compared to control rats. Two months before the terminal phase of chronic renal failure (CRF), T/A ratio abruptly declined. T and its precursors on the 4-ene pathway, A, progesterone (P) and 17-hydroxyprogesterone were evaluated in pampiniform plexus testicular vein (PPTV) and in peripheral blood (PV) in end stage uremic rats (blood urea greater than 30 mmol/l, creatinine clearance less than 0.5 ml/min). Under basal conditions, all steroids but peripheral P were significantly lower in uremic rats than in controls as well as T/P and A/P ratios. After human chorionic gonadotropin (hCG) stimulation, T concentration in PV and PPTV remained highly significantly lower than in controls whereas T precursor concentrations were partially corrected by hCG administration. T/P ratio remained lower than in controls whereas A/P ratio was not significantly lower than in controls. Those data show a decline in all the steps of T biogenesis in uremic rats in basal conditions. The defect in 17 beta-hydroxysteroid dehydrogenase evidenced by T/A decrease at the end stage of CRF seems of primary testicular origin as it is not corrected by hCG administration as shown by T/P and A/P ratios in PPTV and in PV.  相似文献   

5.
We described the topography and morphometry of the testicular artery, pampiniform plexus veins, and indirect connections between them in the spermatic cord of the bull. Sixty microcorrosive casts of bovine spermatic cords were analyzed macroscopically, by stereomicroscopy, and by scanning electron microscopy. The average size of the testicles was 94.6 × 49.7 × 54.7 mm. The testicular artery formed a superiorly pointed cone‐like structure with its base fixed to the proximal part of the gonad. The artery gave off one or two branches to the head of epididymis and to the deferens duct. The pampiniform plexus originated from intra‐tunical veins. Veins of the pampiniform plexus were of smaller diameter but larger number than intra‐tunical ones. The density of the veins of the pampiniform plexus was 9.37 ± 1.07 mm?2. The testicular vein began 90–121 mm above the superior pole of the testis. In 2.9% of specimens, the testicular vein was doubled. Numerous anastomoses among veins of pampiniform plexus were observed. Additionally, indirect anastomoses between the testicular artery and pampiniform plexus veins formed by the capillary network of the vasa vasorum of the testicular artery were visualized by scanning electron microscopy. In all cases, narrowings in the casts of the precapillary vessel were observed. We also documented the vasa vasorum of the testicular artery in bulls. The density of these vessels was 22.87 ± 11.48 mm?2. The indirect arteriovenous connections together with the presence of circular constrictions of the lumen in precapillary vessels may play a role in testicular blood flow regulation. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.  相似文献   

6.
In an attempt to determine whether defective testicular testosterone (T) biosynthesis may be associated with a varicocele, an experimental study was performed in adult rats whereby a unilateral left varicocele was surgically created. At 2, 4, 8, and 12 wk following the creation of the varicocele, intratesticular T as well as the activities of three (17 alpha-hydroxylase, 17,20-desmolase, and 17 beta-hydroxysteroid dehydrogenase) of the five enzymes in the delta 4 pathway of testicular T biosynthesis were measured. Intratesticular T (ng/g testis +/- SEM) in the left testis decreased significantly from 121 +/- 21 in the control group to 59 +/- 8 in the two-wk varicocele group (p less than 0.01), and remained significantly suppressed throughout the experimental period. The T concentrations in the right testis paralleled those in the left in both the control and varicocele animals. At 2 wk following the creation of the varicocele, the activity (nmol/min/testis +/- SEM) of the 17,20-desmolase enzyme decreased significantly, from 115 +/- 8 in the left testis of control rats to 87 +/- 6 in the left testis of the varicocele animals (p less than 0.025), and remained low throughout the 12 weeks of the study. The activity of the 17 alpha-hydroxylase enzyme was significantly decreased at the 8th and 12th weeks of the study, while the 17 beta-hydroxysteroid dehydrogenase activity did not show any significant change during the study period. The enzyme activities in the right testis paralleled those in the left testis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
The variations in oestrogen levels which occur in men with septic shock were determined and analysed in terms of the changes seen in the levels of other steroid hormones of testicular and adrenal origin. The concentrations of the hormones, oestrone (E1), oestradiol (E2), testosterone (T), delta 4-androstenedione (delta 4), cortisol (F) and progesterone (P4) were determined by radioimmunoassay. The serum levels of cholesterol, triglycerides, phospholipids and non-esterified fatty acids (NEFAs) were also determined. Two groups of male septic shock patients were studied within the first 24 h following the admission to the Intensive Care Unit. Group I (n = 24) patients died. Group II (n = 22) patients recovered. Both groups were compared to a control group (n = 44) of healthy men. In group I patients, serum E1 levels were 3900 +/- 900 pmol/l, 12-fold higher than controls (296 +/- 22 pmol/l) [P less than 0.001], serum E2 levels were 880 +/- 170 pmol/l, 6-fold above control levels (158 +/- 30 pmol/l) [P less than 0.001] and serum T levels were 1.7 +/- 0.3 nmol/l, 11-fold lower than in controls (18.7 +/- 1.9 nmol/l) [P less than 0.001]. Serum P4 and F levels were slightly increased (P less than 0.05) and delta 4 androstenedione levels were unchanged. Groups II serum estrogen levels (814 +/- 350 pmol/l) [P less than 0.01] were higher than controls and serum T levels were 2-3 times less than control levels (5.5 +/- 2 nmol/l) [P less than 0.01]. The group II serum P4, F and delta 4 androstenedione levels did not differ from control levels. The levels of cholesterol, triglycerides, phospholipids and NEFAs were all decreased to similar, significant, degrees in both groups of shock patients. The dramatic increase in E1 levels associated with the decrease in T suggests an adrenal-testicular relationship with possible potentiation of aromatization of adrenal or testicular androgens in men in septic shock. The determination of serum E1 and T during septic shock in men could form the basis for prognostic estimations of septic shock severity and for a new therapeutic approach to shock.  相似文献   

8.
We have developed an easy and rapid method of reverse-phase high-performance liquid chromatography (HPLC)-UV spectrometry for measuring adrenal delta 4-steroids. Three female neonates with adrenal 21-hydroxylase deficiency (2 salt-losers and 1 simple virilizer), two of whom were recalled by neonatal mass-screening for congenital adrenal hyperplasia (CAH), were diagnosed using this method. Changes of several adrenal steroids were examined in these patients before and after treatment with hydrocortisone. Before treatment, the cortisone and cortisol peaks were very low and those of 17 alpha-hydroxyprogesterone (17-OHP) and 21-deoxycortisol (21-DOF) were high in all 3 patients (17-OHP: 79.9-997 nmol/l, 21-DOF: 83.7-324 nmol/l). The androstenedione peak was also high in 2 of them. A peak produced by 21-deoxycortisone, which is a product of oxidation of 21-DOF at the C-11 position, was also detected in all cases (14.5-297 nmol/l). After treatment, all of these abnormally elevated delta 4-steroids decreased or disappeared. This new method is thought to be valuable for the rapid diagnosis of CAH, and especially for use in neonatal mass-screening for CAH.  相似文献   

9.
Blood flow to the testis, measured by the133-Xenon isotope clearance technique, initially increased after rams were exposed to elevated (32°C) temperature. However, after 5 and 7 days continuous exposure, blood flow decreased significantly. Similar changes in blood flow to the testis were found during whole body exposure to elevated temperature, or when the temperature of the testis was increased by scrotal heating. After one week of heating the wall of the spermatic artery in the middle region of the pampiniform plexus had thickened, and the arterial lumen had decreased significantly. The PGF 2 content in the testis of rams exposed to elevated temperature increased significantly. It is tentatively postulated that the higher levels of PGF 2 in the testis of rams exposed to elevated temperature may be responsible for impaired spermatogenic function by constricting the spermatic artery in the pampiniform plexus region and thereby reducing blood flow to the testis.Published with approval of the Director of Kentucky Agricultural Experiment Station as Journal Article 75-5-150.Presented at the Seventh International Biometeorological Congres, 17–23 August 1975. College Park, Maryland, U.S.A.  相似文献   

10.
Ketoconazole, an orally active antifungal drug, is known to inhibit testicular androgen production both in vitro and in vivo. The aim of the present study was to examine the effect of ketoconazole and 13 other imidazole drugs on rat testicular microsomal 17 alpha-hydroxylase, 17,20-lyase, 3 beta-hydroxysteroid dehydrogenase-isomerase (3 beta-HSD-I) and 17 beta-hydroxysteroid oxidoreductase (17 beta-HSOR). The order of decreasing inhibitory effect (determined from Ki values) on 17 alpha-hydroxylase (substrate [3H]progesterone; Km = 89 +/- 0.65 nmol/l; SEM, n = 8) was bifonazole (Ki = 86 +/- 3.3 nmol/l; SEM, n = 4) greater than ketoconazole (160 +/- 4.92) greater than clotrimazole (170 +/- 5.81) greater than miconazole (599 +/- 7.22) greater than econazole (688 +/- 6.98) greater than tioconazole (901 +/- 1.71) greater than isoconazole (1090 +/- 6.96) and on 17,20-lyase (substrate, [3H]17 alpha-hydroxyprogesterone; Km = 250 +/- 0.75 nmol/l; SEM, n = 8) was bifonazole (56.5 +/- 3.4) greater than clotrimazole (81.5 +/- 3.1) greater than ketoconazole (84 +/- 3.5) greater than miconazole (243 +/- 6.3) greater than econazole (325 +/- 5.1) greater than tioconazole (505 +/- 5.2) greater than isoconazole (610 +/- 6.34). However, these imidazole drugs did not inhibit the 3 beta-HSD-I or 17 beta-HSOR activities. A common structural feature of the imidazole drugs having an inhibitory effect was the presence of one or more aromatic rings on the imidazole side chain. In contrast, the imidazole drugs having the imidazole ring fused to a benezene ring, i.e. benzimidazoles (astemizole, mebendazole, thiabendazole) and those having an aliphatic side chain on the N-1 of the imidazole ring (carbimazole, metronidazole, nimorazole, tinidazole) did not inhibit 17 alpha-hydroxylase, 3 beta-HSD-I or 17 beta-HSOR enzyme activities. However some did inhibit 17,20-lyase activity but only at high concentrations. The results of the present study suggest that some imidazole drugs may be useful in clinical situations requiring the suppression of androgen production, for example in the treatment of hormone-dependent prostatic cancer.  相似文献   

11.
An original method for 5-androsten-3beta,17beta-diol (A-diol) measurement using an antiserum against A-diol-16-CMO-BSA is described. A-diol and testosterone (T) were determined by radioimmunoassay methods in spermatic and peripheral venous plasma of nine normal subjects during surgical intervention for inguinal hernia repair. In spermatic venous plasma the levels of T and A-diol were, respectively, 25.9 +/- 13.3 and 4.8 +/- 5.1 microgram/100ml (mean +/- SD) with an A-diol/T ratio of 0.19 +/- 0.15 (mean +/- SD); in peripheral plasma the levels of T and A-diol were, respectively, 269 +/- 58 and 91 +/- 25 ng/100 ml (mean +/- SD) with an A-diol/T ratio of 0.35 +/- 0.12 (mean +/- SD) significantly different from spermatic venous plasma (p less than 0.01). From these data a mean testicular A-diol secretion of about 0.70 mg/24 h can be calculated: this value corresponds approximately to the 50% of the blood production rate (BPR) of this steroid. So it can be assumed that a large amount of A-diol in systemic blood comes from sources outside the male gonad.  相似文献   

12.
The present study determined the source and regulation of 17 alpha-hydroxyprogesterone (17-OHP4) during mid-late baboon pregnancy. Serum 17-OHP4 (ng/ml) in 5 untreated baboons increased from low values at mid-late gestation to a mean (+/- SEM) of 0.49 +/- 0.02 during the final 20 days of gestation. Fetectomy of 5 baboons resulted in serum 17-OHP4 concentrations which declined to and remained at baseline. Serum 17-OHP4 concentrations were 5- to 10-fold greater (P less than 0.001) in the uterine, utero-ovarian, and umbilical veins than peripherally. Apparently the fetal adrenal provides precursors for placental 17-OHP4 formation because the fetal adrenal gland develops delta 5-3 beta-hydroxysteroid dehydrogenase only late in gestation, and because the fetal adrenal and not the placenta has the capacity for 17-hydroxylation. Thus, at mid-late gestation the placenta appears to supply a major, and at term the corpus luteum a minor portion of the total 17-OHP4. Administration of the estrogen antagonist ethamoxytriphetol (MER-25, 15 mg/kg BW) to 4 baboons did not affect 17-OHP4 during mid-late gestation, when the placenta was the only source of 17-OHP4. However, MER-25 resulted in serum 17-OHP4 concentrations (ng/ml) at term which were greater (1.08 +/- 0.10, P less than 0.001) than in untreated baboons (0.49 +/- 0.02). Prior removal of the corpus luteum of pregnancy in 4 animals subsequently given MER-25 prevented this rise in 17-OHP4. This suggests that the marked elevation in 17-OHP4 observed near term after MER-25 administration was of luteal origin and that antiestrogen enhanced 17-OHP4 secretion by the corpus luteum.  相似文献   

13.
The suggestion that androgens may regulate testosterone (T) production in rat Leydig cells by a receptor-mediated feed-back mechanism, led us to investigate whether in vivo the absence of testicular androgen receptors, as it occurs in testicular feminization (TF), may modify the characteristic testicular response observed in men and prepubertal children after a single dose of hCG. Subjects consist of: 1) six normal men, 2) two adult patients with the complete form of androgen insensitivity syndrome (TF), 3) 12 normal prepubertal boys, 4) one prepubertal boy with the same form of TF. Each subject received i.m. a single dose of hCG 3500 IU/m2 b.s. and blood samples were collected basally and 2, 4, 24, 48, 72 and 96 hours after the hormonal stimulus. Serum levels of T, 17 alpha hydroxyprogesterone (17OHP) and 17 beta estradiol (E2) were measured at each collection time. In normal men a significant increase in T (M +/- SE) was observed at 4 h (758.6 +/- 135 ng/dl, P less than 0.05) and a more significant increase at 48 h (1082 +/- 60.3 ng/dl, P less than 0.001). E2 and 17OHP peaked significantly at 24 h (81.5 +/- 9.6 pg/ml and 460.7 +/- 90.9 ng/dl respectively). This response pattern is characteristic of the testicular desensitization which occurs in normal man after a single hCG dose. The same response pattern has been observed in the two TF adult patients suggesting that human testicular desensitization in vivo does not depend on androgen receptors.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
Serum sex hormone binding globulin (SHBG), testosterone (T), DHEA sulphate (DHEA-S), androstenedione (AD) and delta 5-androstene-3 beta,17 beta-diol sulphate (5-ADIOL-S) levels were measured by specific radioimmunoassay in 16 girls presenting with premature adrenarche (PA) and in 14 normal girls. Mean levels of steroids measured were elevated, and SHBG significantly depressed, in the girls with PA, with values (mean +/- SE) for DHEA-S (1.73 +/- 0.17 vs 0.25 +/- 0.06 mumol/l), 5-ADIOL-S (104 +/- 8 vs 31 +/- 4 nmol/l), AD (0.89 +/- 0.06 vs 0.62 +/- 0.04 nmol/l), and T (0.49 +/- 0.03 vs 0.23 +/- 0.06 nmol/l). SHBG levels were 68 +/- 6 vs 108 +/- 5 nmol/l, and the free androgen index [100 x T (nmol/l) divided by SHBG (nmol/l)] was 0.89 +/- 0.17 vs 0.22 +/- 0.01. These studies show that SHBG is depressed in girls with premature adrenarche; with the increased testosterone levels, this results in a markedly elevated free androgen index, a measure of testosterone which is bioavailable to target tissue. This may be compounded by the elevated levels of 5-ADIOL-S in girls with PA since its role may be as a prohormone for more potent androgens (testosterone, 5 alpha-dihydrotestosterone) in target tissues such as pubic skin.  相似文献   

15.
Ketoconazole (K) is an antifungal imidazole derivative which has been shown to be a potent inhibitor of testosterone (T) biosynthesis in rodents and humans. To study the effect of K on rat testicular steroidogenesis we measured the activities of five testicular microsomal steroidogenic enzymes in K-treated rats and controls. Thirty male adult rats were given either 2 mg K or water every 12 hours by mouth during 5 days. Mean testicular weight was similar in both groups of animals. The K-treated group had a T serum concentration of 83 +/- 14 ng/dL whereas it was 94 +/- 16 ng/dL in the control group (NS). The K-treated animals had decreased activities of the 3 beta-hydroxysteroid dehydrogenase (830 +/- 48 vs 2,245 +/- 109 pmol/mg protein/min, P less than 0.001), 17-hydroxylase (243 +/- 5 vs 676 +/- 17 pmol/mg protein/min, P less than 0.001), 17-ketosteroid reductase (31 +/- 2 vs 169 +/- 7 pmol/mg protein/min, P less than 0.001), and aromatase enzymes (92 +/- 6 vs 123 +/- 7 pmol/mg protein/min, P less than 0.01). The 17,20-desmolase activity was similar in both groups of animals (210 +/- 4 vs 171 +/- 18 pmol/mg protein/min). We conclude that K given orally to rats inhibits the activity of several testicular steroidogenic enzymes.  相似文献   

16.
Three questions were asked in an attempt to understand how testosterone (T) concentration in the veins of the remaining testis can double within 24 h after hemicastration in the mature rat without a change in plasma luteinizing hormone (LH) levels. These three questions (and their answers) were: 1) Can the testicular hemicastration response occur in hypophysectomized rats? Answer, No. 2) Does LH binding to the testis increase after hemicastration? Answer, No. 3) Is there a neural route to the testis alternate to the superior spermatic plexi? Answer, Yes, apparently there is, since hemivasectomy contralateral to the excised testis partially suppressed the testicular hemicastration response (150.4 +/- 13.2 ng/ml in hemicastrated, sham- hemivasectomized rats [n = 18] vs. 109.4 +/- 11.6 ng/ml in hemicastrated, hemivasectomized rats [n = 18], P less than 0.026). It was concluded that LH was probably necessary to the testicular hemicastration response but that its presence did not provide a mechanism. The response was mediated at least partly through the inferior spermatic nerves associated with the vas deferens. A possible reason, although highly speculative, for failure to previously block the testicular hemicastration response by bilateral denervation of the superior spermatic plexi (Mock and Frankel , 1982) was that during the 12-wk interval between denervation and hemicastration, testicular innervation functionally transferred from the superior spermatic to the inferior spermatic nerves.  相似文献   

17.
M G Forest 《Hormone research》1976,7(4-5):260-273
A highly specific antiserum raised against the 3(O-carboxymethyl)oxime of 17alpha-hydroxyprogesterone (17-OHP) was produced in rabbit and used in the development of a specific radioimmunoassay (RIA) for 17-OHP which included a celite chromatography. Methods allowing the measurement of plasma 17-OHP levels either separately or in combination with that of several plasma androgens (testosterone, delta4-androstenedione and dehydroepiandrosterone) are described. Moreover, RIA meabsurement of plasma 17-OHP levels with or without chromatographic (celite column) purification gave comparable results (mean +/- SD) in 29 normal adult males (118 +/- 34 ng/100 ml) and 35 normal adult females (follicular phase: 46+/- 16 ng/100 ml); luteal phase: 241 +/- 71 ng/100 ml).  相似文献   

18.
A new case of testicular 17 ketosteroid reductase (17 KSR) deficiency without gynecomastia was investigated. Delta4 androstenedione (15.6 ng/ml) was ten times the normal range, unchanged after dexamethasone administration. In contrast, plasma testosterone (4.1 ng/ml) was in the low normal male range and plasma dehydroepiandrosterone (4.2 ng/ml) was normal. Plasma luteinizing hormone and follicle-stimulating hormone were increased (162 and 470 ng/ml LER 907 respectively). After adrenal suppression and human chorionic gonadotropin stimulation, the increase of delta4 androstenedione was in contrast with the inertia of testosterone. In spermatic venous plasma delta4 androstenedione level (293.2 ng/ml) was very high and testosterone level (7.1 ng/ml) a hundred times below the normal mean. Plasma estrone (124 pg/ml) was increased and estradiol (22 pg/ml) was normal. In spermatic venous plasma estrone was elevated and estradiol very low (1380 and 32 pg/ml respectively). It is the third case of 17 KSR deficiency where the lack of E2 increase explains the absence of gynecomastia.  相似文献   

19.
Flutamide, hydroxyflutamide, RU23908 and cyproterone acetate (CPA) inhibited rat testicular microsomal 17 alpha-hydroxylase and 17,20-lyase activities in vitro. The Km of [3H] progesterone for 17 alpha-hydroxylase was 45 +/- 0.62 nmol/l (+/- SEM, n = 12) and the Km of [3H] 17 alpha-hydroxyprogesterone for 17,20-lyase was 192 +/- 0.42 nmol/l (+/- SEM, n = 12). The Ki values for 17 alpha-hydroxylase, determined from Lineweaver-Burk plots were 102 +/- 3.2 mumol/l (+/- SEM, n = 6), 363 +/- 3.8 mumol/l (+/- SEM, n = 6), 118 +/- 1.4 mumol/l (+/- SEM, n = 6) and 123 +/- 2.1 mumol/l (+/- SEM, n = 6) for flutamide, hydroxyflutamide, RU23908 and CPA respectively. Flutamide and CPA were mixed-type inhibitors, whereas hydroxyflutamide and RU23908 were competitive inhibitors of 17 alpha-hydroxylase activity. Ki values for 17,20-lyase were 33 +/- 3.1 mumol/l (+/- SEM, n = 6), 112 +/- 3.1 mumol/l (+/- SEM, n = 6), 69 +/- 4.4 mumol/l (+/- SEM, n = 6) and 71 +/- 3.2 mumol/l (+/- SEM, n = 6) for flutamide, hydroxyflutamide, RU23908 and CPA, respectively. Inhibition was found to be competitive in each case. Although the characteristic action of anti-androgens is at the receptor level, these results demonstrate that anti-androgens may also have inhibitory effects on androgen biosynthesis which could prove to be of clinical significance.  相似文献   

20.
Serum sulphates of 5-androstene-3 beta,17 beta-diol (5-ADIOL-S), 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-DIOL-S) and dehydroepiandrosterone (DHEA-S), unconjugated androstene-dione (AD) and testosterone (T), sex hormone binding globulin (SHBG), free androgen index (FAI), 17 alpha-hydroxyprogesterone (17OHP), luteinising hormone (LH) and follicle stimulating hormone (FSH) were measured by specific radioimmunoassay in 28 hirsute women with polycystic ovarian disease (PCO) and in normal women (n = 73). Mean levels of steroids measured were significantly elevated, and SHBG significantly depressed, in the women with PCO with values (mean +/- SE) for 5-ADIOL-S (516 +/- 51 vs 267 +/- 10 nmol/l), 3 alpha-DIOL-S (130 +/- 9 vs 52 +/- 2 nmol/l), DHEA-S (7.3 +/- 0.5 vs 4.4 +/- 0.2 mumol/l), AD (11.3 +/- 1.1 vs 3.4 +/- 0.2 nmol/l), T (3.3 +/- 0.2 vs 1.5 +/- 0.1 nmol/l) and 17OHP (5.1 +/- 0.8 vs 2.8 +/- 0.2 nmol/l). SHBG levels were 31 +/- 2.9 vs 65 +/- 2.5 nmol/l, and the free androgen index [100 x T (nmol/l) divided by (SHBG nmol/l)] was 12.5 +/- 1.4 vs 2.4 +/- 0.1. The mean LH to FSH ratio was also elevated at 2.8 +/- 0.3. These studies suggest that the measurement of 5-ADIOL-S and DHEA-S may indicate adrenal gland involvement in PCO while 3 alpha-DIOL-S appears to be a reflection of peripheral androgen metabolism. A comprehensive biochemical profile of PCO should thus include the analysis of these sulphoconjugates as well as unconjugated steroids.  相似文献   

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