摘要:

The locations of steroid binding sites with specificities for 17β‐oestradiol, progesterone and testosterone have been examined on human spermatozoa by autoradiography. The binding sites were not evenly distributed over the entire surface of human spermatozoa. They were more densely located on the midpiece of the tail, less on the head and neck, and least on the principal‐ and end pieces of the tail. The binding sites for 17β‐oestradiol were specific, with3H‐17β‐oestradiol being displayed by unlabelled 17β‐oestradiol, but less readily displaced by either progesterone or testosterone. The binding sites for testosterone were less specific than those for 17β‐oestradiol or those for progesterone. Both 17β‐oestradiol and progesterone were good competitors for testosterone binding sites, while the binding of3H‐progesterone was easily displaced by 17β‐oestradiol, but less readily displayed by testosterone. Since there was preferential binding of these steroids to the mid‐piece, and strong competition for binding between 17β‐oestradiol and progesterone, these studies appear to provide information on the sites of action for the reported effects of these and related steroids on spermatozoal mot

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00685.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

The concentration of spermatozoa in human semen has been assessed by counting in the microscope with a hemocytometer and by counting with the Coulter Counter ZF. The Coulter Counter was supplied with a 100‐channel pulseheight analyzer, Channelyzer C‐1000, and a tape‐punch for further handling of data in a desk‐computer. It was found that the number of spermatozoa (less than 106per ml) was over‐estimated with the Coulter Counter. By subtraction of the non‐spermatozoan background with the aid of mathematical curve‐fitting procedures, these values could be corrected. To allow such an adequate analysis without the use of pulse‐height analyzer and computer, the background corrections were simulated for the relative number of counts obtained at specified settings of the threshold levels (T) and other variables on the Cou

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00686.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

In vitro studies were performed to investigate the accessibility of acrosin to various proteinase inhibitors inside the intact acrosome of testicular, ejaculated, and uterine human spermatozoa. As test system the gelatin plate assay was used. For this assay it was shown formerly that a correlation exists between the size of the digested lysis areas (halo formation) and acrosin activity estimated with synthetic substrates. In addition, saturation of the gelatin substrate membranes with acrosin inhibitors including highly specific ones before application of spermatozoa completely prevented halo formation indicating that the gelatinolytic activity of human spermatozoa is caused exclusively by acrosin. When human spermatozoa were incubated with various acrosin inhibitors (concentration: 1 mmol/1) prior to application to the gelatine membrane, reduction of halo formation could not be observed, however. This result indicates that most of the tested acrosin inhibitors (9 naturally occurring protein inhibitors, 2 microbial peptide inhibitors, 19 synthetic inhibitors) were unable to penetrate the acrosomal membr:ines of rrsticular, ejaculated. and uterine human spermatozoa. Only 2 inhibitors caused moderate up to complete inhibition of the gelatinolytic activity of the spermatozoa if applied in concentrations between I and 10 mmul/l: [he proteinase inhibitor aprotinin and the synthetic inhibitor NPCR (4‐nitrophenyl 4‐˜uanidini, benzoate). Obviously, human acrosomal membranes seem to be especially impenetrable to proteins, polypeptides. and synthetic agents. Those acrosin inhibitors penetrating the human sperm head membranes are either too toxic or the local concentration necessary for effectice ncrosin inhihition in vivo cannot be achieved within the male or female genital tract secrelions. Therefore. arrosin inhibitors cannot be used for human contraceptioti at present. Thus it is mandatory to continue the search for suitable acrosin inhibitors with low toxicity easily penetrating into the intact sperm acros

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00687.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Surface‐radioiodinated bull spermatozoa were ultrasonicated and fractionated by Percoll‐gradient centrifugation. The different fractions obtained were solubilized and analyzed by SDS‐polyacrylamide gel electrophoresis. Three fractions containing sperm heads, midpieces, and membranes and small fragments of the principal pieces were obtained. The electrophoresis revealed 5 main peaks representing the radioiodinated surface proteins with molecular weights of 80000–90000 (Ia), 68000–75000 (Ib). 42000–47000 (II), 33000–37000 (III) and 15000–18000 (V) from the intact spermatozoa as well as from each sperm fragment fraction. The major differences between fractions were in the relative magnitudes of the peaks. The peak II characteristically dominated in the head fraction, but was very small in the midpiece fraction. The results from the present study suggest that the peak II seen in the intact spermatozoa is mainly located on the head plasma membrane and that the differences in the sperm surface properties may be due to the uneven distribution or surface exposure

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00688.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Nine volunteers were treated with metoclopramide (10 mg T.D.S.) for 4 weeks. Prolactin levels rose both in serum and in seminal plasma 1 week following the initiation of metoclopramide administration. At this point in time, sperm density and total sperm count increased about twofold. Thereafter, levels of prolactin slowly decreased while sperm density and total sperm count fell back to initial values.

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00689.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

FSH responsive adenylyl cyclase (AC) activities were examined in both homogenates and membrane particles from 9–71 days old rat testes, and FSH binding was determined in membrane particles from the same animals. FSH responsive AC was measured in the presence of either GTP (0.04 mM) or the non‐metabolizable GTP analogue, GMP‐P(NH)P (0.04 mM). From days 9 and 11 there was a gradual decrease in both basal and FSH stimulated AC activities and a very similar decrease in FSH binding. The relative stimulation by FSH, however, was fairly constant (2–3 fold stimulation). The excellent correlation between specific FSH binding and FSH responsive AC activities during sexual maturation does not support the notion that uncoupling of the FSH receptors from the AC is a primary reason for the attenuated FSH response during pubertal development. The age dependent decrease in both basal and FSH stimulated AC activities during sexual maturation is a reflection of the relative increase in germ cells (containing no FSH receptors and FSH responsive AC). The LH/hCG responsive AC in membrane particles from the same ages showed an age dependent increase in both absolute activities and relative responses, probably indicating the increased number of Leydig cells in the developing

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00690.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

High levels of hCG occur in testicular interstitial fluid (IF) following injection of the hormone, and the proportion that is taken up by the testis has been assessed by comparing the concentrations in IF of [125I]hCG and [125I]BSA (i.e. an inert protein) in rats treated with the same total dose of hCG. Adult male rats were injected with a total dose of either 0.5 or 45.5 IU hCG and which included either [125I]hCG or [125I]BSA, and were killed between 2 and 40 h later when the concentrations of the labelled proteins in plasma, IF and testicular tissue were assessed.Treatment with either dose of hCG increased IF levels in the testis at 4–24 h after injection although this increase was much greater (350% v 61%) with the higher dose of hCG. In rats injected with [125I]hCG, the ratio of radioactivity in testicular tissue to that in IF (T/IF) varied between 0.3 and 2.1 depending on the total injected dose of hCG and the time after injection, whilst in rats injected with the same amounts of unlabelled hCG together with [125I]BSA, the T/IF ratio never exceeded 0.09 and remained constant with time. In the latter group, the IF/plasma ratio of [125I]BSA was always significantly higher than in rats injected with [125I]hCG, irrespective of the total dose of hCG injected. The difference between the IF/plasma ratios for [125I]BSA and [125I]hCG gives a measure of how much of the hCG has been removed by testicular uptake. The results show that following injection of either 0.5 or 45.5 IU hCG, the temporal pattern of testicular hCG‐uptake from IF is similar, although proportionately more (50–59%) of the hCG in IF has been taken up within 24 h of injection of the low dose of hCG than with the high dose (32–52%). It is concluded that testicular IF is an important medium for the transport of injected hCG from the blood to the Leydi

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00691.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Determinations of fructose, zinc, magnesium and acid phosphatase were performed in seminal plasma from male partners in 225 barren couples. No specific changes in the concentrations of these substances could be observed in men showing either visible or palpatory abnormalities of the external genitals, the prostate or of the seminal vesicles, extreme changes in the number, morphology or motility of the sperms, increased sperm antibody titre or abnormal serum levels of testosterone or gonadotrophins. However, when the prostatic fluid contained numerous leukocytes, the concentrations of zinc, magnesium and acid phosphatase were significantly lower than in men having a cytologically normal prostatic fluid. Determinations of these substances may thus be of aid in the diagnosis of chronic prostatovesiculitis.

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00692.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Testosterone concentration has been measured in spermatic and peripheral venous plasma obtained during surgery from a total of 25 prepubertal boys affected either by inguinal hernia (Group I; N = 6; age range 2–8 years) or unilateral undescended testis (Group II; N = 19; age range 5–11 years). Median spermatic venous testosterone level was 58.7 ng/dl) (range 14.0–120.8 ng/dl) in Group I and 43.2 ng/dl (range 12.2–267.5 ng/dl) in Group II: median peripheral testosterone level was 4.9 ng/dl (range 2.3–15.4 ng/dl) and 5.6 ng/dl (range 1.1–89.3 ng/dl) in Group I and II, respectively. The difference between the spermatic and peripheral level was statistically significant in both groups (P<0.01 in Group I andP<0.001 in Group II). These results indicate that the prepubertal human testis secretes testosterone, even if in a very low amount. It is also suggested that this secretion can be responsible for LH inhibition in prepu

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00693.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY

摘要:

Gonadotrophin and testosterone levels were measured in male foetal rats at the 21st day of gestation 30 min following administration of LRH. The releasing hormone was administered by 3 different routes: subcutaneously as a single injection to the pregnant rat; subcutaneously as 12 times repeated injection to the pregnant rat from 16th–21st day of gestation: direct injection into the amniotic cavity. Three different doses of 1, 5, and 10 μg/kg were used. The single administration to the dam was without effect. Repeated doses resulted in a significant dose‐dependent elevation of mean foetal LH: 163 μng/ml in the control animals and 133, 256, and 363 ng/ml in the 1, 5, and 10 μg/kg LRH group resp. Intra amnial injections significantly increased FSH and LH levels, but only those of FSH were clearly dose‐dependent. A mean of 390 ng/ml in the control group was observed, with 1 μg/kg LRH FSH was elevated to 723 ng/ml, at 5 μg/kg to 928 and at 10 μg/kg to 1017 ng/ml. Testosterone levels were not significantly altered. Our results demonstrate that the pituitary of foetal rats is able to respond to LRH in the same manner as ad

ISSN:0105-6263    

DOI:10.1111/j.1365-2605.1981.tb00694.x

出版商:Blackwell Publishing Ltd    

年代:1981

数据来源: WILEY