Showing papers in "Archives of Andrology in 1981"
TL;DR: Changes in the patterns of lectin binding have been noted during sperm maturation in the epididymis, during capacitation, and after the acrosome reaction, and these studies contribute to the understanding of mechanism that may mediate these transformations.
Abstract: Studies involving the use of lectins to probe the spermatozoon surface are reviewed, with particular emphasis on mammalian spermatozoa and their various transformations during maturation, capacitation, and the acrosome reaction. Although the numbers of lectin binding sites on spermatozoa are generally comparable to those of many somatic cells, the distribution of most lectins thus far studied is highly restricted to certain domains of the cell surface. These domains are often related to specific underlying morphological entities such as the acrosome, postacrosomal region, mitochondria associated with the middle piece, and so on. Changes in the patterns of lectin binding have been noted during sperm maturation in the epididymis, during capacitation, and after the acrosome reaction, and, in some instances, these studies contribute to the understanding of mechanisms that may mediate these transformations. This is particularly true of situations where lectin labeling or binding studies have been used in conju...
154 citations
TL;DR: The effects of zinc therapy on plasma testosterone, dihydrotestosterone, and sperm count were studied in 37 patients with idiopathic infertility of more than five years duration and there was no conception observed.
Abstract: The effects of zinc therapy on plasma testosterone (T), dihydrotestosterone (DHT), and sperm count were studied in 37 patients with idiopathic infertility of more than five years duration. In the f...
77 citations
TL;DR: The acrosome reaction was induced in ram, rabbit, and human sperm by incubating with the ionophore A23187 plus calcium ions, although the percentage of reacted sperm was different for each species: 90% in ram; 60% in rabbit; and 69% in man.
Abstract: The acrosome reaction was induced in ram, rabbit, and human sperm by incubating with the ionophore A23187 plus calcium ions, although the percentage of reacted sperm was different for each species: 90% in ram, 38% in rabbit, and 69% in man. Fusion of the outer acrosomal and plasma membranes of ram and rabbit sperm formed vesicles, but in human sperm only the outer acrosomal membrane was involved in vesiculation. Acrosin was lost from ram, rabbit, and human sperm after treatment with ionophore plus calcium. Ionophore alone induced the reaction in only 35% of ram sperm, 20% of human sperm, and 12% of rabbit sperm. On exposure to A23187 alone, the acrosome of unreacted rabbit sperm bulged and the acrosome and nuclear membrane of human sperm were often lifted away from the nucleus. The percentage of mammalian sperm undergoing the acrosome reaction in the presence of calcium alone, was very low.
54 citations
TL;DR: Gossypol enhanced respiration and abolished forward motility of boar spermatozoa and the effective concentration was 10(-5) M, similar to that reported in its uncoupling of oxidative phosphorylation in rat liver mitochondria.
Abstract: Gossypol, the active component in cottonseed oil, inhibits spermatogenesis in many mammals. Gossypol enhanced respiration and abolished forward motility of boar spermatozoa. The effective concentration was 10-5 M, similar to that reported in its uncoupling of oxidative phosphorylation in rat liver mitochondria. Its antifertility effect may be a combination of the effect on the developing spermatids as well as that on spermatozoal motility.
54 citations
TL;DR: The mammalian testes have several mechanisms to propel the nonmotile spermatozoa in the seminiferous tubules through the rete testis into the epididymis, and the efflux of fluids and sperm from the testis appears to closely parallel spermiation.
Abstract: The mammalian testes have several mechanisms to propel the nonmotile spermatozoa in the seminiferous tubules through the rete testis into the epididymis. These include (a) contractions of the testicular capsule and the seminiferous tubules and (b) fluid flow through the excurrent ducts resulting from active transport of fluids and electrolyte into the seminiferous tubules from the extracellular space. The efflux of fluids and sperm from the testis appears to closely parallel spermiation. An increased output of fluid may result from prostaglandins (PGF2 alpha) and possibly oxytocin (not all species respond to oxytocin) as a result of capsular contractions compressing and expelling the fluid from the tubules. Seminiferous tubular contractions do not result from nervous stimulation but are linked to PGs and cyclic nucleotide generation. They are regulated to some extent by androgens and the lesser response of the tubules to 5 alpha-dihydrotestosterone compared to testosterone can be explained by their interaction with androgen binding protein and their action on phospholipase A2 activity for PG synthesis.
45 citations
TL;DR: Intensive shaking and centrifugation significantly increased the percentage of dead spermatozoa, as confirmed from the combined supravital staining and MEP technique.
Abstract: Fresh seminal specimens from 48 normospermic donors were subjected to shaking and centrifugation at various intensities and durations, and their effect on sperm motility was determined objectively by the multiple exposure photography (MEP) method. Shaking for 15 sec by mechanical vibrator did not induce any drop in sperm percentage of motility, while shaking for 30 to 180 sec was followed by immediate drop of this parameter. Sperm velocity increased for a short duration in all shaken specimens, after which it dropped considerably in most cases. Following centrifugation below 330 g for 10-20 min, sperm motility was almost unaffected. However, there was a significant drop in sperm motility after specimens were subjected to rates above 580 g for the same time duration. Intensive shaking and centrifugation significantly increased the percentage of dead spermatozoa, as confirmed from the combined supravital staining and MEP technique.
41 citations
TL;DR: The physical properties and hormonal regulation of testosterone estradiol binding globulin (TeBG) and androgen binding protein (ABP) are reviewed and speculations are presented for the functional significance of these proteins.
Abstract: The physical properties and hormonal regulation of testosterone estradiol binding globulin (TeBG) and androgen binding protein (ABP) are reviewed. Brief mention is made of prostatic binding protein. The discussion focuses on the mechanism of action for these proteins in androgen secretion, transport, and absorption and androgen binding models. Speculations are presented for the functional significance of these proteins.
35 citations
TL;DR: With cessation of antiserum treatment testicular function and fertility were completely restored to normalcy, indicating that the observed effect was specifically due to FSH deprivation.
Abstract: Adult fertile male bonnet monkeys (Macaca radiata) were continuously deprived of endogenous follicle stimulating hormone (FSH) support for 240 days by injecting them with 1 ml of characterized monkey antiserum to oFSH every 48 hr; control monkeys received during the same period normal monkey serum instead. Testicular function was assessed at periodic intervals by (a) carrying out differential counting of sperm in the ejaculate obtained and (b) determining the hyaluronidase activity as well as in vitro 3H thymidine incorporation into DNA of testicular tissue removed at biopsy. Both the quality (viability and motility) of the sperms voided and the total sperm counts showed marked decreases as a function of time of immunization, the first significant reduction being noted by 100 days. FSH deprivation affected both the biochemical parameters used to test testicular functionality they being reduced at ∼200 days by 50%-60%. The fertility of these monkeys was evaluated at periodic times after 90 days of treatment by means of mating studies. FSH deprivation had rendered the monkeys incapable of impregnating any of the females used. Testosterone and luteinizing hormone (LH) levels remained unchanged following FSH antiserum injection. With cessation of antiserum treatment testicular function and fertility were completely restored to normalcy, indicating that the observed effect was specifically due to FSH deprivation. This study thus provides conclusive evidence for the involvement of FSH in maintenance of testicular function and fertility in the adult male primate.
34 citations
TL;DR: The clinical, diagnostic, and therapeutic aspects of the male hyperprolactinemia syndrome are described as related to sexual dysfunction and infertility.
Abstract: Elevated levels of prolactin(PRL) are associated with gonadal dysfunction in men and women, but the relationship between PRL levels and gonadal activity is best defined in women. The purpose of this review is to summarize and discuss the influence of PRL on the male reproductive function in normaprolactinemia and to describe the clinical, diagnostic, and therapeutic aspects of the male hyperprolactinemia syndrome as related to sexual dysfunction and infertility.
30 citations
TL;DR: Cholesterol and phospholipid exchange between sperm cells and seminal plasma was shown by the striking correlation between the lipid composition of seminal plasma with that of sperm cells.
Abstract: Normal and pathological semen were studied with regard to cholesterol and phospholipid content of sperm cells and seminal plasma. Spermatozoa from pathologic semen have similar concentrations of phospholipid-phosphorous and significantly higher cholesterol concentration than spermatozoa from normal semen. However, only oligoasthenospermic spermatozoa showed a significantly higher cholesterol/phospholipid ratio. Azoospermic seminal plasma showed the lowest values of both cholesterol and phospholipids, but the ratio of cholesterol to phospholipids was equal to that in normal spermatozoa. No significant difference was found in the cholesterol concentration of seminal plasma from oligoasthenospermic, asthenospermic, and normospermic subjects and only asthenospermic plasma showed a significantly lower concentration of this compound. Cholesterol and phospholipid exchange between sperm cells and seminal plasma was shown by the striking correlation between the lipid composition of seminal plasma with that of sperm cells.
30 citations
TL;DR: The human penis can well erect without closure of the efferent vein from the corpora cavernosa, and the performance of carvernosography was carried out to determine whether the venous closure is indeed a prerequisite to human penile erection.
Abstract: Inquiry was made into the theory that closure of the efferent vein from the corpora cavernosa is essential for erection of the human penis. To determine whether the venous closure is indeed a prerequisite to human penile erection, two tests were carried out in men: (1) direct infusion of 133Xe into corpora cavernosa and (2) performance of cavernosography. In each case, penile erection was induced by providing the subject with sexual stimulation. The behavioral changes were studied through the 133Xe clearance curve and the contrast medium, respectively. When the penis remained flaccid, the 133Xe clearance curve followed a gentle path and the contrast medium could be noted within the penis for a relatively long period. However, on erection with sexual stimulation, the 133Xe clearance curve fell rapidly instead of following the gentle course expected in the case of venous closure. Also, the contrast medium quickly flowed out of the corpora cavernosa. The human penis therefore can well erect without closure o...
TL;DR: Follicle stimulating hormone (FSH) binds to the plasma membranes of Sertoli cells and, apparently, spermatogonia; the hormone may then be taken into the cytoplasm of its target cells and metabolized there.
Abstract: Follicle stimulating hormone (FSH) binds to the plasma membranes of Sertoli cells and, apparently, spermatogonia; the hormone may then be taken into the cytoplasm of its target cells and metabolized there. In the immature testis, binding of FSH to Sertoli cells leads to activation of adenylate cyclase, formation of cyclic AMP (cAMP), and activation of a cAMP-dependent protein kinase. There is a subsequent increase in the rates of RNA, protein, and DNA synthesis. Normal adult testis is unresponsive to FSH, one reason being the destruction of cAMP by a phosphodiesterase. After hypophysectomy of adult animals this enzyme disappears and FSH is again able to stimulate RNA and protein synthesis. Other factors contributing to the insen-sitivity of the mature testis are an FSH binding inhibitor, a protein kinase inhibitor, and in-activation of FSH.FSH increases the formation by Sertoli cells of structural proteins and an androgen-binding protein (ABP) that the Sertoli cells secrete into the extracellular fluid su...
TL;DR: High-resolution analysis showed successive peaks of relative concentration of the labels over the endoplasmic reticulum, Golgi apparatus, and apical plasma membrane, thus confirming that protein synthesis and excretion follow the usual pathway in the principal cells all along the epididymis.
Abstract: The synthesis and excretion of newly formed proteins in the principal cells of the head, body, and tail of the epididymis were studied by quantitative autoradiography in light and electron microscopy. Adult mice were killed from 5 min to 6 hr after intravenous injection of tritiated leucine, lysine, and arginine. The labels were taken up early and in greater amounts in the principal cells of the head. Radioactivity decreased in the cells of all three segments throughout the first hour following administration of the tracers. Thereafter, it increased in the lumen. High-resolution analysis showed successive peaks of relative concentration of the labels over the endoplasmic reticulum, Golgi apparatus, and apical plasma membrane, thus confirming that protein synthesis and excretion follow the usual pathway in the principal cells all along the epididymis. However, since a radioactivity peak occurred as early as 15 min over the apical membrane of cells in the head, it is likely that part of the endoplasmic reticulum-canalicular and poor in polysomes-is involved independently in the synthesis and rapid transport of newly formed proteins.
TL;DR: "Inhibin"-like protein, partially purified from the human prostate, was similar to that obtained from human seminal plasma under identical conditions and concentration of inhibin in human prostate was tenfold higher as compared to human testis and was active biologically and immunologically.
Abstract: “Inhibin”-like protein, partially purified from the human prostate, was similar to that obtained from human seminal plasma under idential conditions. Concentration of inhibin in human prostate was tenfold higher as compared to human testis and was active biologically and immunologically. The presence of a high amount of inhibin in prostate seems to be unique in humans. Further inhibin concentration in benign prostatic hypertrophy tissue increased by tenfold in comparison to normal or cancerous tissue. Hence determination of serum level of inhibin may be used as a therapeutic tool to monitor prostate diseases.
TL;DR: High doses of estrogen given for treatment of prostatic cancer or modulation of reproductive function not only reduce testosterone secretion but also interact with the liver, changing the secretion of various plasma proteins and causing several undesirable side effects.
Abstract: Estrogens in the male are secreted by the testes and derived extragonadally from the aromatization of certain androgens. In some brain regions critical for the control of gonadotropin secretion and behavior, androgens may be aromatized to estrogens within the cells that are regulated. Estrogen may have other physiological roles on the testes to control testosterone secretion and on accessory sex glands to promote both fibromuscular growth and secretion. High doses of estrogen given for treatment of prostatic cancer or modulation of reproductive function not only reduce testosterone secretion but also interact with the liver, changing the secretion of various plasma proteins and causing several undesirable side effects. The hypothalamus, pituitary, testes, accessory sex glands, and liver all contain an apparently identical protein, the estrogen receptor, which may mediate the actions of estrogen.
TL;DR: AC desensitization preceded LH receptor downregulation and may support the notion that uncoupling of the catalytic subunit of the AC from Leydig cell LH/hCG receptors is a requirement for subsequent receptor internalization.
Abstract: A single s.c. injection of 75IU of human chorionic gonadotropin (hCG) into adult male rats caused a transient desensitization of the LH/hCG responsive adenylyl cyclase (AC) in membrane particles from rat testis. Two hours after the injection of hCG, LH/hCG responsive AC was reduced by 40%, whereas LH binding was still normal. After 24 hr LH/hCG responsive AC was lost, whereas LH binding only showed a marginal decrease. During the next 2-3 days there was a gradual loss of LH/hCG receptors, which reached a nadir at day 4 (14% of control levels). At day 6 and 9 following the hCG injection LH/hCG receptors and LH/hCG responsive AC gradually returned towards normal. Fluoride (F∼) stimulated AC activity showed only minor changes throughout the period investigated. The initial loss of AC responsiveness to hCG was associated with maximal levels of circulating hCG. However, desensitization persisted for several days after hCG was cleared from the circulation. AC desensitization preceded LH receptor downregulation ...
TL;DR: A double blind study was carried out with placebo and dopaminergic agents in 100 patients with male diabetic sexual impotence, finding sexual activity was improved in 50% of cases after 3-4 dihidroxifenilalanine and 10% of those of the placebo group.
Abstract: A double blind study was carried out with placebo and dopaminergic agents in 100 patients with male diabetic sexual impotence. In basal conditions, mean serum FSH, LH, PRL, and T levels did not significantly differ from those found in a normal control group. No significant variations with the exception of PRL reduction were observed after use of the dopaminergic agents. Sexual activity was improved in 50% of cases after 3-4 dihidroxifenilalanine and 10% of those of the placebo group. In patients with bromocriptine, 20% improved their sexual function without changes in those receiving placebo.
TL;DR: Results of this study indicate that the major effect of LH upon blood concentration if T in the bull is usually exerted within 1 hr of a LH surge, and failure of some LH peaks to be followed by T peaks suggests that the secretion of LH and T inThe bull may be subject to modulation by adrenocortical hormones and other intrinsic and extrinsic factors.
Abstract: Temporal interrelationships of endogenous peripheral blood concentrations of corticosteriods (CS), luteinizing hormone (LH), and testosterone (T) were evaluated in bulls. Concentrations of CS, LH, and T were quantitated in blood samples collected at hourly intervals via jugular cannula from four bulls during a single 24-hr period in January and again in June. Alterations in hormone profile characteristics were noted within bulls between January and June. An increased number of LH peaks and increased area beneath entire 24-hr LH profile suggested that LH secretion was higher during the June sampling period than the January sampling period. However, no significant alteration in T secretion in June was observed, as number of T peaks and area under T peaks were essentially unchanged relative to January. An inconsistent relationship between secretion of LH and T was observed in June, with only 47% of LH peaks associated with elevations in concentration of T whereas in January 80% of LH peaks were associated wi...
TL;DR: The mechanism by which hyperprolactinemia interferes with sperm production and the effect of bromocriptine on this mechanism is discussed.
Abstract: Hyperprolactinemia associated with male infertility or impotence was found in ten patients. Mean prolactin level was 83 +/- 49 ng/ml (range 46-26- ng/ml). The etiological bases of the hyperprolactinemia were a microadenoma in one patient, liver disease in two, and idiopathic in seven patients. Bromocriptine treatment, 2.5-7.5 mg daily for 8-16 weeks lowered prolactin to normal levels in all patients. Three oligoasthenospermic subjects showed a marked increase in sperm motility; their wives conceived within 5-8 weeks of treatment after longstanding infertility. Two of these women gave birth to normal babies and one aborted in the first trimester of pregnancy. The mechanism by which hyperprolactinemia interferes with sperm production and the effect of bromocriptine on this mechanism is discussed.
TL;DR: There was a positive correlation between zinc and androgens contents, while the opposite was suggested by the data in the epididymis, and patients on estrogen therapy showed much lower androgen values in the two organs.
Abstract: Tissue testosterone, dihydrotestosterone, and zinc concentrations have been determined in testis and epididymis of 13 patients with carcinoma of the prostate, 1 patient with carcinoma of the penis, and 3 patients with carcinoma of the prostate on estrogens. The 13 patients not receiving estrogens had the following testicular levels: testosterone, of 529 +/- 63.1 ng/g (mean +/- SE); dihydrotestosterone, 23.7 +/- 2.58 ng/g; and zinc 62.2 +/- 7.6 micrograms/g. The epididymal levels were as follows: testosterone, 40.6 +/- 3.4 ng/g; dihydrotestosterone, 20.5 +/- 2.36 ng/g; and zinc, 67.2 +/- 11.1 micrograms/g. Patients on estrogen therapy showed much lower androgen values in the two organs but zinc was not changed significantly. Concentrations of androgens were not significantly different in the epididymal fractions of caput, corpus, and cauda. In testis, there was a positive correlation between zinc and androgens contents, while the opposite was suggested by the data in the epididymis. Even though these patients were not normal, there was no evidence of testicular or epididymal disturbances.
TL;DR: Theoretical considerations such as leakage of sperm, obstruction and narrowing of the anastomosis, suggest that a stentless technique with exact approximation of mucosal edges will result in a better success rate.
Abstract: Many different surgical techniques of vasovasostomy can be successful. Many factors, both technical and nontechnical, play a role in determining pregnancy. Theoretical considerations such as leakage of sperm, obstruction and narrowing of the anastomosis, suggest that a stentless technique with exact approximation of mucosal edges will result in a better success rate. Careful macroscopic surgery with the use of fine suture material, and experience on the part of the surgeon, will give good results and pregnancy rates of up to 50%. Microsurgery becomes quite important when the anastomosis is performed in the convoluted portion of the vas and epididymis. The microscope allows more mobility in permitting one to determine if the patient has a block proximal to the vasectomy site, and then bypass these blocks. Conventional macroscopic techniques do not allow for this freedom of choice. Factors other than technique are also important and are discussed.
TL;DR: Digestion of human sperm chromatin with micrococcal nuclease reveals an 160 base pair DNA fragment that is further degraded to a series of DNA fragments remarkably similar to the microcOCcal nUClease digestion products of eukaryote somatic cellular chromatin, suggesting a nucleosomal structure for human sperm Chromatin.
Abstract: Digestion of human sperm chromatin with micrococcal nuclease reveals an 160 base pair (bp) DNA fragment that is further degraded to a series of DNA fragments remarkably similar to the micrococcal nuclease digestion products of eukaryote somatic cellular chromatin DNase I digestion of human sperm chromatin also yields an identical pattern of DNA fragments to that observed upon DNase I digestion of somatic chromatin These data, together with earlier electron microscopic observations, suggest a nucleosomal structure for human sperm chromatin
TL;DR: Nonspecific esterase of mouse epididymis has previously been studied histochemically, using alpha naphthyl-acetate and 5-bromoindoxyl acetate techniques, as well as certain inhibitors.
Abstract: Nonspecific esterase of mouse epididymis has previously been studied histochemically, using alpha naphthyl-acetate and 5-bromoindoxyl acetate techniques, as well as certain inhibitors. Epithelial cell types of the epididymis have been characterized, and certain esterase isozymes identified in specific cell types. In this study, at least one such isozyme, previously characterized in a particular cell type, is shown to be androgen dependent. When mice of different strains were castrated or treated with antiandrogens, the characteristic histochemical reaction product disappeared or was greatly reduced. Androgen treatment of castrated animals caused the reaction in the cells concerned to return to normal. This method can now be applied to the study of epididymides of genetically sex-reversed chromosomal females, to analyze genetic control of X-chromosomal activation.
TL;DR: A simple human chorionic gonadotropin (hCG) test to measure Leydig cell function is described and preliminary tests in 10 adult males showed a maximal increase in plasma testosterone between the third and fifth day that was confirmed in a further 20 normal subjects when measured once on the fourth day.
Abstract: A simple human chorionic gonadotropin (hCG) test to measure Leydig cell function is described. Plasma testosterone was measured on two occasions, once before intramuscular injection of 10,000 IU of hCG and again four days later. Preliminary tests in 10 adult males showed a maximal increase in plasma testosterone between the third and fifth day that was confirmed in a further 20 normal subjects when measured once on the fourth day. Except for 2 patients with hypospermatogenesis, 24 showed a good response and the mean increase was comparable with that in normal males. Nineteen patients with Klinefelter's syndrome usually had lower basal levels and showed a poor response, with the exception of six patients in whom there were moderate but definite increases. Twelve patients with hypogonadotropic hypogonadism had basal testosterone concentrations below 1 ng/ml and eight responded poorly to hCG stimulation. However, four patients showed a moderate but definite response.
TL;DR: There is no positive conclusion whether vasectomy leads to cell mediated immunity to spermatozoa and presence and effects of circulating immune complexes following vasectomy are discussed with reference to reported increased incidence of atherosclerosis and auto-immune orchitis in experimental animals.
Abstract: In more than 50% of men, vasectomy leads to auto-immune pathology. The auto-immune response to sperms following vasectomy is triggered by the phagocytosis of sperm in the epididymis. In the humoral immune response, sperm agglutinating, sperm immobilizing, and antibodies to sperm nuclear protamines occur, as early as 3-4 days after vasectomy. The incidence reaches 60-70% within 1 year and remains almost the same even after 20 years. Presence and effects of circulating immune complexes following vasectomy are discussed with reference to reported increased incidence of atherosclerosis and auto-immune orchitis in experimental animals. There is no positive conclusion whether vasectomy leads to cell mediated immunity to spermatozoa.
TL;DR: DNA synthetic activity was studied by autoradiography in unilaterally cryptorchid and contralateral intact intact testes in mice, indicating that type A spermatogonia did not temperature sensitive in DNA synthesis in vivo.
Abstract: DNA synthetic activity was studied by autoradiography in unilaterally cryptorchid (abdominal) and contralateral intact (scrotal) testes in mice. Nongerm cells were inactive in DNA synthesis in both the cryptorchid testis and the intact control. Labeling indices of undifferentiated type A spermatogonia did not show any differences, indicating that type A spermatogonia are not temperature sensitive in DNA synthesis in vivo.
TL;DR: Observations suggest that T-lymphocyte in the male genital tract are surveilled by HuSePl and lack of inhibitory material could induce an immunologic response by spermatozoal antigens.
Abstract: Human seminal plasma, (HuSePl) is inhibitory to mitogen (PHA-M, Con-A, and PWM) lymphocyte activation. The inhibition does not require the continuous presence of HuSePl. Lymphocyte cultures remain inhibited after 24-hr contact with HuSePl and subsequent washings. Addition of fresh autochthonous lymphocytes or T cells but not B cells can restore the mitogenic activity of HuSePl-inhibited lymphocyte cultures. These observations suggest that T-lymphocyte in the male genital tract are surveilled by HuSePl and lack of inhibitory material could induce an immunologic response by spermatozoal antigens.
TL;DR: L-Arginine stimulation of ejaculated rabbit sperm motility was quantitated by a spectrophotometric procedure and the percent stimulation was inversely proportional to the initial motility of the sperm sample.
Abstract: l-Arginine stimulation of ejaculated rabbit sperm motility was quantitated by a spectrophotometric procedure. Stimulation of sperm motility was correlated to arginine concentration, incubation time, and pH. A maximum increase in motility of 85% was apparent for up to 7 hr with 10−1 M l-arginine. A significant decrease in the ability of l-arginine to stimulate sperm motility was observed at pH values less than 7.0 and greater than 8.0. The percent stimulation was inversely proportional to the initial motility of the sperm sample.
TL;DR: The temporal associations of elevated concentrations of CS and P with basal LH and T before EE, absence of T response to endogenous LH peaks, and the temporary absence of episodic LH andT peaks after EE, suggest that endogenous adrenal steroids may modulate secretion of T in the bull.
Abstract: Temporal relationships among serum concentrations of corticosteroids (CS), luteinizing hormone (LH), progesterone (P), and testosterone (T) were examined in ten bulls exposed to the stress of electroejaculation (EE). Concentrations of CS and P increased concomitantly among bulls to peak levels by 15 min post-EE and then declined to pre-EE levels between 2 and 4 hr after EE. Total number of LH and T peaks decreased from 24 and 18, respectively, during the 12-hr pre-EE period to 11 and 14 during the 12-h post-EE period. Mean concentration of LH decreased after EE until 4 hr post-EE when episodic LH secretion resumed and concentrations of CS and P had declined to pre-EE levels. Similarly, mean concentration of T declined after EE and then increased 6-8 hr post-EE in response to resumption of LH secretion. The temporal associations of elevated concentrations of CS and P with basal LH and T before EE, absence of T response to endogenous LH peaks, and the temporary absence of episodic LH and T peaks after EE, suggest that endogenous adrenal steroids may modulate secretion of T in the bull.
TL;DR: The study shows that interstitial tissue possesses both ADH and ALDH, which are essential for the respective metabolism of ethanol and acetaldehyde, and that the seminiferous tubules possesses greater affinity for the metabolism of acetaldehyde than that of theinterstitial tissue.
Abstract: The distribution of both alcohol (ADH) and aldehyde-dehydrogenase (ALDH) was studied in the rat testis. Testicular ADH was mainly localized into the interstitial tissue. Testicular ALDH activity was distributed between the interstitial tissue and the seminiferous tubules with greater activity measured in the former component. The apparent Km for ADH in the whole testis was greater than that measured in the interstitial tissue. A low Km value was determined for ALDH in the seminiferous tubules, compared to a higher mean Km value for this enzyme in the interstitial tissue of the testis. The study shows that interstitial tissue possesses both ADH and ALDH, which are essential for the respective metabolism of ethanol and acetaldehyde, and that the seminiferous tubules possesses greater affinity for the metabolism of acetaldehyde than that of the interstitial tissue.