bluuebunny/crossref_metadata_2025 huggingface dataset:
The temporal response of rat testes to hCG stimulation during sexual maturation
Authors: Hodgson Yvonne M. , de Kretser D. M.
Published: May 2008

Serum testosterone responses to a single sc injection of hCG (25 IU/100 g body weight) were monitored for 5 days in rats throughout sexual maturation (22–70 days). Two hours after hCG injection serum testosterone levels rose in 22, 37 and 53 day‐old animals and remained elevated for 2 days, returning to control levels on day 3. This response differed markedly from the biphasic secretion of testosterone reported for adult animals. In 70 day‐old animals the serum testosterone response approached that seen in adult animals. Testosterone levels were elevated 2 h after hCG injection (25.4 ± 2.5 ng/ml) and declined significantly at 12 and 24 h to 17.1 ± 1.0 and 16.1 ± 3.4 ng/ml, respectively. Testosterone levels tended to increase again on days 2 and 3 (19.9 ± 2.8 and 21.1 ± 3.5 ng/ml, respectively) but the increase was not statistically significant. This response differed markedly to the biphasic secretion of testosterone reported for adult animals. In vitro patterns of basal and hCG‐stimulated testosterone secretion by decapsulated testes following a single hCG injection also changed during sexual maturation. In 22 day‐old animals the testes exhibited refractoriness to in vitro hCG stimulation at 12 h, but testes from 37 day old rats were refractory from 2 to 24 h. In vitro testosterone responses of testes from 53 and 70 day‐old rats were similar to that reported for adult rats with a period of refractoriness from 12 h to 2 days. This study demonstrates that during sexual maturation in the rat alterations occur in the temporal patterns of testosterone secretion in vivo and in vitro following hCG stimulation.
Effect of treatment with different doses of bromocriptine on plasma profiles of prolactin, gonadotrophins and testosterone in mature male rats and mice
Authors: Rao M. Ramachandra , Bartke A. , Parkening T. A. , Collins T. J.
Published: May 2008

The influence of different doses of bromocriptine (CB‐154) on plasma levels of prolactin (Prl), FSH, LH and testosterone (T) in mature male rats and mice was studied. Daily subcutaneous administration of 360 μg of CB‐154 in sesame oil was sufficient to induce maximal suppression of plasma Prl levels in mature male rats whilst subcutaneous implantation of two pellets of CB‐154 and cholesterol, each containing approximately 6 mg CB‐154, was effective in suppressing serum Prl levels in mature rats for at least four weeks. This was accompanied by a significant elevation of plasma levels of LH and FSH. A similar dose‐response study in mature male mice suggested that relatively higher doses of CB‐154 are required to suppress plasma levels of Prl in this species, although large doses of CB‐154 can still increase plasma levels of gonadotrophins and T in male mice.
Haemodynamic aspects of left‐sided varicocele and its associaton with so‐called right‐sided varicocele
Authors: Mali Willem P. Th. M. , Arndt Jan Willem , Coolsaet Bo L. R. A. , Kremer Jan , Oei Hong Y.
Published: May 2008

A method has been developed which uses a radionucleotide to demonstate retrograde bloodflow in the testicular vein and the size of the pampiniform plexus in patients with a varicocele. This method and phlebography were both performed in 71 patients. The radionucleotide method was reliable in showing retrograde flow in the testicular vein and enabled quantification of the size of the pampiniform plexus. On the right side, however, retrograde bloodflow or an enlarged pampiniform plexus were not found in any of the 71 patients. Misinterpretation of phlebographic and radionucleotide studies are probably responsible for recent reports on the frequent occurrence of right sided varicocele.
Evaluation of the morphology of sperm in urine of adolescent boys
Authors: Weissenberg R. , Hirsch M. , Shemesh J. , Modan M. , Lunenfeld B.
Published: May 2008

The morphology of spermatozoa in the first morning void of boys aged 12–16 years was evaluated. The results suggest that the number of cells having normal morphology increases with advancing age. Thus, the percentage of boys with greater than 45% normal sperm was 26% at the age of 12–13, increasing to 51% at the age of 15–16.
Sialoglycoproteins of ejaculated human spermatozoa and seminal plasma
Authors: Wongkome C. , Chulavatnatol M.
Published: May 2008

Ejaculated human sperm were found to possess three major sialoglycoproteins with molecular weights of 30 000, 14 000 and 12 000 and one minor species of 18 000. Liquefied seminal plasma from normal donors contain two major sialoglycoproteins with molecular weights of 17 000 and 15 000 and two minor species of 70 000 and 54 000. In contrast, the liquefied sperm‐free semen of vasectomized men had two major species of sialoglycoproteins of 20 000 and 18 000 daltons plus two minor species of 54 000 and 40 000.
Local regulation of Leydig cells by the seminiferous tubules. Effect of short‐term cryptorchidism
Authors: Bergh Anders , Damber Jan‐Erik
Published: May 2008

Unilateral cryptorchism was induced in adult rats for 24 h, and its effect on testicular morphology and intratesticular testosterone concentration after hCG‐stimulation were studied. In seminiferous, tubules from abdominal testes an increased number of degenerating germ cells was noted in stages XIV–III of the spermatogenic cycle and Sertoli cells contained an increased amount of lipid droplets in stages XIV–VIII. However, germ cells and Sertoli cells from tubules at other stages of the cycle appeared unaffected. In scrotal testes the size of peritubular Leydig cells varied in phase with the spermatogenic cycle. The largest cells were found adjacent to stage VII–VIII and the smallest adjacent to stage XI–XII. In abdominal testes no stage‐dependent variation in the size of peritubular Leydig cells was seen. Perivascular Leydig cells were of equal size in abdominal and scrotal testes. The testicular testosterone concentration following stimulation with a low dose of hCG was significantly lower in abdominal testes. It is suggested that the seminiferous tubules locally modulate Leydig cell function and that the stage specific stimulatory influence from stage VII–VIII is rapidly lost during experimental cryptorchidism.
Aminopeptidase A in reproductive organs of the male rat: evidence for high activity in the posterior lobe of the prostate.
Authors: Vanha‐Perttula Tapani , Agrawal Yashpal , Jauhiainen Anneli
Published: May 2008

Of the reproductive organs of the male rat a high level of hydrolysis of α‐L‐glutamyl‐β‐napthylamide (GluNA) and α‐L‐aspartyl‐β‐naphthylamide (AspNA) in the presence of Ca2+ (5mM) (aminopeptidase A) was found in the posterior lobe of the prostate. Histochemically, this enzyme was localized in the epithelial cells of acini, which were grouped in the dorsal part and sharply separated from non‐active acini in the anterior part of the lobe. A single peak of Ca2+‐activated GluNA and AspNA hydrolysis was obtained after chromatofocusing at pI 4.9 and on anion exchange chromatography this activity eluted at 0.09 M NaCl. After gel filtration on Sepharose 6B a major peak of activity was found at the elution volume (Ve/Vo= 2.28). In all of these fractionation procedures aminopeptidase A was partially or totally overlapped by other aminopeptidases hydrolysing various amino acid‐β‐naphthylamides. A pooled enzyme preparation gave an optimum at pH 7.3. The hydrolysis of GluNA was markedly enhanced in the presence of Ba2+, Ca2+ and Sr2+, but the hydrolysis of AspNA was activated only by Ca2+ and Sr2+. Castration caused a significant decrease in the hydrolysis of GluNA by the posterior lobe, but did not influence the low levels of activity in other parts of the prostate or in the seminal vesicles.
Effect of gossypol‐acetic acid on calcium transport and ATPase activity in plasma membranes from ram and bull spermatozoa
Authors: Breitbart H. , Rubinstein S. , Nass‐Arden L.
Published: May 2008

The effects of gossypol acetic acid on the activity of Mg‐ATPase and Ca‐Mg‐ATPase and on calcium uptake by plasma membranes from ram and bull spermatozoa were examined. The three parameters were almost completely inhibited by 10 μM gossypol for both ram and bull sperm. In order to assess the effects of higher gossypol concentrations isolated membrane vesicles were loaded with calcium by operating the ATP‐dependent calcium pump after which gossypol was added and calcium uptake followed. At 10 μM gossypol, additional calcium uptake was 85% inhibited while at 40 μM a release of the accumulated calcium was observed. The inhibitory effect of 10 μM gossypol was almost completely reversible by simple dilution of gossypol‐treated membranes, whilst at 40 μM the effect was only 50% reversible. The data show a high degree of similarity between bull and ram, suggesting minimal differences between the two species as far as the structure and function of the sperm plasma membrane is concerned.
Testiscular response to human chorionic gonadotrophin in men with non‐tumoural hyperprolactinaemia
Authors: Padrón Rubén S. , Más Jorge , de Acosta Oscar Mateo
Published: May 2008

The change in plasma levels of testosterone and oestradiol‐17‐β following a single intramuscular injection of 6000 IU hCG was studied in 7 men with non‐tumoural hyperprolactinaemia and who were without clinical and/or laboratory evidence of hypogonadotrophism. These values were compared to the response of normal males to hCG. Plasma samples were obtained at 0, 2, 4, 24, 48, 96, 144, 192 and 240 h after hCG injection. The early and late phases of the plasma testosterone to hCG in hyperprolactinaemic patients were comparable to those of the controls, although the maximum and relative increment was somewhat diminished (5.0 ± 1.2 vs 7.2 ± 2.1 ng/ml; P < 0.05, and 1.8 ± 0.2 vs 2.3 ± 0.5 ng/ml; P < 0.02, respectively). The plasma oestradiol response to hCG was not different between the two groups, but the maximum and relative incement was higher in the hyperprolactinaemic patients (135.9 ± 20.6 vs 97.1 ± 11.9 pg/ml; P < 0.05, and 4.9 ± 0.6 vs 3.1 ± 0.5 pg/ml; P < 0.01, respectively. These findings suggest that the testosterone response to exogenous gonadotrophin is impaired in patients with non‐tumoural hyperprolactinaemia. Whether this impairment is related to the higher increment in plasma levels of oestradiol remains to be elucidated. The data presented favour the hypothesis that in hyperprolactinaemic men, the prolactin exerts a direct action at the testicular level.
Association between infertility following reversal of vasectomy and the presence of sperm agglutinating activity in semen
Authors: Sutherland P. D. , Matson P. L. , Masters J. R. W. , Pryor J. P.
Published: May 2008

A statistically significant association between infertility, following reversal of vasectomy, and the presence of sperm agglutinating activity in post‐operative semen samples has been demonstrated in a retrospective study. Sperm agglutinating activity was measured using a microtitration assay, and the number of positive samples rose from 3/78 (4%) pre‐operatively. to 34/134 (25%) post‐operatively. High titres (≥ 1:32) of agglutinating activity were observed only when viable sperm were present in the ejaculate. Positive semen titres were obtained only when parallel serum samples were positive at titres of ≥1:256. Conception only occurred in the partner of one man whose seminal plasma contained agglutinating activity, but 22/34 (65%) of the men whose semen lacked such activity were fertile.
In vivo study of LDH isoenzyme activities in heart, liver and testis cytosols of gossypol‐treated rats
Authors: Steiner M. , Frick J. , Rovan E.
Published: May 2008

LDH isoenzyme activities of heart, liver and testis homogenates were measured in rats treated for 15 or 30 days with 30 mg gossypol acetic acid/kg body weight daily, a dose which severely suppressed sperm motility. No differences in LDH activities of the examined organs were found in comparison with control animals. LDH‐X, the main LDH isoenzyme in spermatozoa and testicular germ cells from primary spermatocytes onwards was also unaffected. These results contrast with in vitro experiments on human, rabbit, and boar spermatozoa, purified bovine LDH‐X and rat testis homogenate which show dose‐dependent inhibition of LDH‐X after incubation with gossypol. Our results therefore suggest that inhibition of LDH by gossypol is not the primary cause of sperm immotility.
Foetal meiosis in the testis of the rodent Octodon degus
Authors: Rojas M. A. , Morales B. , Esponda P.
Published: May 2008

Different stages of meiotic prophase have been studied in foetal testes of the rodent, Octodon degus, using the light and electron microscope. Special attention was focused on the ultrastructural morphology of these meiotic cells in comparison to pre‐spermatogonia of foetal testes and meiotic spermatocytes of the adult male testis. Meiosis occurs in only a few cells located among fibroblasts of the tunica albuginea or in the region of the gonadal blastema. The foetal meiotic process resembles adult meiosis in its ultrastructural characteristics; typical pachytene synaptonemal complexes and leptotene or diplotene axial elements appear associated to the chromatin. This process occurs at the same foetal age that meiosis commences in the ovary, thus reinforcing the idea that both meiosis‐inducing and meiosis‐preventing substances are secreted in both sexes. The intra‐or extracordonal localization of the germ cells would be an important factor in determining the cells' response to these substances.
Purification of testosterone‐oestradiol‐binding globulins from mammalian sera by anion‐exchange high performance liquid chromatography
Authors: Cheng C. Yan , Bardin C. Wayne , Nagendranath N. , Escobar N. , Han Arthur C. , Musto Neal A. , Gunsalus Glen L.
Published: May 2008

Testosterone‐oestradiol‐binding globulin (TeBG) has been isolated from serum or plasma of several species using procedures that yielded highly purified protein, but which required multiple and tedious chromatographic steps. In this report we describe a procedure for the isolation of TeBG which involves two chromatographic steps: androgen affinity chromatography followed by anion‐exchange high performance liquid chromatography (anion‐exchange HPLC). The purity of the final product was confirmed by silver staining following fractionation on sodium dodecyl sulphate‐containing polyacrylamide gels. The size heterogeneity and specific binding activity of TeBGs purified from human, rabbit, or bull serum (or plasma) by this technique was indistinguishable from preparations obtained by conventional chromatography. The present technique shortened the entire purification procedure to about 5 working days and yielded milligram quantities of highly purified protein. Bases on our experience with serum or plasma from the human, rabbit, and bull, this approach should be suitable for isolation of TeBG from a wide range of species.
On the origin of prostaglandins in human seminal fluid
Authors: Bendvold E. , Svanborg K. , Bygdeman M. , Norén S.
Published: May 2008

To evaluate the origin of seminal prostaglandins, genital tract fluids were analysed for prostaglandin content in two clinical situations. Six patients delivered semen samples before and after vasectomy. In these patients the prostaglandin concentration remained essentially unchanged although sperm density decreased to zero. In another patient secretory products from the testis and epididymis, and the ejaculate representing mainly the secretion of the seminal vesicles and the prostate gland, were collected separately. Secretions obtained from the testis and epididymis did not contain detectable amounts of prostaglandins, whilst in the ejaculate from the same patient the concentration was within normal limits. The results of the study show that the testis and epididymis do not contribute significantly to the prostaglandin content of human seminal fluid. The previous assumption that the seminal vesicles are the main source of seminal prostaglandins is thus supported.
Changes in intratesticular testosterone, cytoplasmic androgen receptors and ABP content of the ram testis after a single endogenous pulse of LH
Authors: Monet‐Kuntz Catherine , Terqui Michel
Published: May 2008

The effects of an endogenous LH pulse on the testicular concentration of testosterone, cytoplasmic androgen receptor content and androgen binding protein (ABP) content was studied in rams. Blood was collected from 36 rams for at least 14 h and their testes then removed. Animals were then grouped according to the interval from their last LH pulse and the time of slaughter. The concentration of testosterone in the testis was highest during the first h following the LH pulse and returned to its baseline within 5 h. There was a 60% reduction in the testicular content of cytoplasmic androgen receptors at 3 h after the LH pulse, followed by slow replenishment. The testicular content of ABP was highest at 4 h after the LH pulse. It is in the testis concluded that the pulsatility of LH and testosterone induces a pulsatile translocation of cytoplasmic androgen receptors.
LDH‐C4 in human seminal plasma and its relationship to testicular function
Authors: Virji Nassim
Published: May 2008

LDH‐C4 is a lactate dehydrogenase isoenzyme specific for spermatocytes, spermatids and spermatozoa. Its presence in seminal plasma therefore stems from its release by one or more of these cell types. LDH‐C4 has been analyzed quantitatively in semen samples from men under different experimental conditions. Incubation of semen at 37°C for up to 6 h did not alter LDH‐C4 activity in seminal plasma. When volunteers donated several semen samples with different time intervals (4 h to 7 days) between the ejaculations, the LDH‐C4 activity showed only moderate variations when expressed per 100 million spermatozoa. The relatively constant relationship between LDH‐C4 activity and the number of sperm in the ejaculate, and the observation that there was no leakage of LDH‐C4 from the ejaculated sperm, indicate that this enzyme originates from the testis. It could, therefore, be a chemical marker reflecting the degree of germ cell degeneration in the seminiferous epithelium in relation to the number of spermatozoa formed during the same time period. In contrast to the small intra‐individual variation for LDH‐C4 activity per 100 million sperm (mean cv = 36.6%, N = 5), there was a large inter‐individual variation. In 79 men with a barren union the mean LDH‐C4 activity was 28.9 nanokatal/100 million sperm (95% confidence limits 0 to 114).
Effects of inhibitory and stimulatory photoperiods and sexual maturation on the ability of hamster testes to respond to hCG in vitro
Authors: Bartke A. , Matt K. S. , Amador A. G. , Klemcke H. G. , Brown D. , Gonzales D. , Hogan M. P.
Published: May 2008

The decrease in gonadal weight produced in adult golden hamsters by exposure to short photoperiods was accompanied by a marked reduction in the ability of the testes to produce testosterone from endogenous precursors in vitro, both without and with hCG stimulation. These changes were significant after 4–7 weeks in short photoperiod (5L: 19D) and were even more pronounced after 17–20 weeks. Production of testosterone in vitro by testes of immature hamsters was comparable to values obtained in adult animals with short photoperiod‐induced gonadal atrophy. Delay of sexual maturation induced by daily injections of bromocriptine was accompained by a further decrease in testicular testosterone production in vitro. Exposure of gonadally‐regressed adult hamsters to a long, stimulatory photoperiod (14L: 10D) produced a rapid and marked increase in testicular testosterone production, which was coincident with the previously demonstrated increase in serum gonadotrophin levels after 1–5 days of photostimulation. Furthermore, testosterone production in vitro by regressed testes of animals exposed to short photoperiod was increased significantly by one large dose of hCG administered 26 h before killing the animals. It is concluded that the suppressive effects of short photoperiods on the ability of the hamster testis to produce testosterone and to respond to hCG stimulation are due to reductions in endogenous LH, FSH and prolactin release, with a consequent loss of testicular LH/hCG receptors and decreased activity of enzymes involved in the biosynthesis of testosterone.
Variable distribution of aminopeptidase A in male reproductive organs of mammals
Authors: Agrawal Yashpal , Vanha‐Perttula Tapani
Published: May 2008

Aminopeptidase A (AP‐A) was analysed in the reproductive organs of the boar, bull, gerbil and man. High hydrolysis of α‐L‐glutamyl‐β‐naphthylamide (GluNA) and α‐L‐aspartyl‐β‐naphthylamide (AspNA) with activation by alkaline earth metals was detected in the ampulla, seminal vesicles, and seminal vesicle secretions of the bull and in the cauda epididymis of the boar and gerbil. In man, weak AP‐A activity was found in all reproductive tissues. Histochemically, AP‐A was localized in the epithelial cells of tissues having a high specific activity for the enzyme. AP‐A was absent from human seminal fluid, whilst bovine seminal fluid had strong, and boar seminal fluid weaker, AP‐A activity. Gel filtration of bull seminal vesicle secretions and seminal fluid, boar seminal fluid or an homogenate of boar and gerbil epididymal cauda and human epididymis and seminal vesicles on Sephacryl S‐300 resulted in a major high‐molecular‐weight activity peak A at Ve/Vo= 1.17 and another low‐molecular‐weight peak B at Ve/Vo= 1.51 (man), 1.62 (boar, bull) or 1.75 (gerbil). This fractionation was not in all cases able to separate AP‐A from aminopeptidase(s), which were active on L‐alanine‐β‐naphthylamide (AlaNA) but showed no activation by alkaline earth metals. Homogenates of bovine epididymis showed only the low‐molecular‐weight GluNA peak B, but two areas of activity for AlaNA hydrolysis. In bovine seminal vesicles and porcine epididymis, AP‐A activity appeared to be linked with the functional maturity of these organs. The high‐molecular‐weight AP‐A (peak A) appeared to be the predominant form in seminal fluid.
Prognostic value of the heterologous ovum penetration test for human in vitro fertilization
Authors: Belkien L. , Bordt J. , Freischem C. W. , Hano R. , Knuth U. A. , Nieschlag E.
Published: May 2008

In order to evaluate the prognostic value of the heterologous ovum penetration test (HOP‐test) the results of this test were compared with the fertilization rate of human ova in a programme for in vitro fertilization and embryo transfer (IVF/ET). Sperm from 29 husbands (23 normozoospermic and 6 with an abnormal semen profile) were exposed on one occasion to approximately 30 hamster ova in the HOP‐test and on 1 to 3 occasions to 1 to 4 preovulatory oocytes obtained from the respective wives. The mean penetration rate (± SEM) of the hamster ova was 43 ± 4% (range: 0–62%) for the normozoospermic men, and 23 ± 6% (range: 0–47%) for the men with abnormal semen profiles. In 20 out of 23 couples in which the husbands were normozoospermic, sperm penetrated the hamster ova as well as they fertilized human ova; however, in one couple, a falsepositive result was obtained (penetration of the hamster ova and no fertilization of the human oocytes) and in one couple a false‐negative result occurred. One negative IVF result was correctly predicted by the HOP‐test. In the 6 patients with disturbed sperm motility no correct positive or negative results were obtained, whilst 4 false‐positive and 2 false‐negative results occurred using the HOP‐test. Although the number of patients with disturbed sperm motility was small, the data suggest that the HOP‐test is of limited value in predicting fertility in an IVF program for couples with reduced fertility.
Laminin and type IV collagen in the human testis
Authors: Pöllänen Pasi P. , Kallajoki Markku , Risteli Leila , Risteli Juha , Suominen Jyrki J. O.
Published: May 2008

Specimens of normal human testis and biopsies from testes with Sertoli‐cell‐only syndrome in which the seminiferous tubules had a remarkably thickened lamina propria, were investigated immunohistochemically using specific antibodies against human laminin and human type IV collagen. In the normal testis, both laminin and type IV collagen were localized to the epithelial basement membranes and the peritubular cell layers. In addition, laminin was found in the Sertoli cells. In the pathological testis, structures representing invaginations of the tubular basement membrane were positive for both laminin and type IV collagen. The presence of laminin and type IV collagen in the myoid cell layers, and laminin in the Sertoli cells from both normal and pathological testis and its indication for the secretion of these substances by the myoid and Sertoli cells is discussed.
Focal testicular destruction following intratesticular injection of glycerol in rats
Authors: Weinbauer Gerhard F. , Galhotra Madan M. , Nieschlag Eberhard
Published: May 2008

Single intratesticular injections of glycerol have been reported to block spermatogenesis in rats without a concomitant change in the serum levels of testosterone and gonadotrophins (Wiebe & Barr 1983, 1984). The present studies were designed in order to confirm these effects and to cast light on the mechanism of action of glycerol. Groups of adult rats received intratesticular injections of either 200 μl distilled water, glycerol or NaCl‐solution. Following the injection of distilled water testicular histology appeared unaltered except for a few empty tubules around the injection site, which probably resulted from injection trauma. Injection of glycerol solution (> 3500 mosmol) caused partial tubule destruction. The most severely affected tubules were devoid of cells and filled with amorphous material. Serum FSH concentrations increased sharply in the first week and remained elevated during the entire study period of 8 weeks. Injection of an equi‐osmolar NaCl‐solution had very similar effects to glycerol on the testes and on hormone levels, suggesting that hyperosmolarity of the injected solutions rather than a specific action of the compounds caused the testicular damage. It is concluded that a single intratesticular injection of glycerol causes severe testicular damage and, in contrast to previous suggestions, appears unsuitable for male fertility regulation.
LDH‐C4 in human seminal plasma and testicular function
Authors: Virji N. , Eliasson R.
Published: May 2008

Lactic dehydrogenase C4 was analysed in human seminal plasma, expressed in nanokatals and related to the sperm count. The LDH‐C4/sperm ratio has previously been shown to reflect the functional integrity of the seminiferous epithelium. In the present study this ratio was related to several other semen variables that reflect various functional or biochemical properties of the spermatozoa or other cell systems. For none of these variables was there a significant linear correlation with the LDH‐C4/sperm ratio, but interesting differences became apparent when the semen samples were subdivided into two groups, those with normal (<20) and those with a high (>20) ratio. For nuclear chromatin stability, oxygen consumption, succinate‐induced increase in oxygen consumption and lipid peroxidation, ***here were significant differences between the two groups. There was no difference between the groups for the staining properities of the DNA‐DNP complex, zinc, fructose and free 1‐carnitine content in the ejaculate, and the zinc/fructose ratio. The results indicate that functional properties of the spermatozoa can be related to the status of the seminiferous epithelium.
Abnormal prolactin secretion in prepubertal boys with hypogonadotrophic hypogonadism — possible involvement in regulation of testicular steroidogenesis
Authors: Dunkel Leo , Huhtaniemi Ilpo
Published: May 2008

The interrelationships of prolactin (Prl), gonadotrophins and testicular steroids were studied in prepuberty in 6 boys with isolated hypogonadotrophic hypogonadism (HH) and 7 boys with incomplete testicular descent (who served as controls). The boys with HH had higher basal serum levels of Prl (P < 0.001) and LH (P < 0.05) than the controls, but lower Prl (P < 0.001) and LH (P < 0.05) responses after metoclopramide + LHRH and lower testosterone responses after hCG. The peak responses of Prl after metoclopramide‐LHRH and of testosterone after hCG correlated strongly in the patients as a whole (r = 0.87, P < 0.001). These observations indicate that, as well as in the gonadotrophins, changes occur in HH in prepuberty in the synthesis and/or release of Prl. The findings also raise the possibility that Prl may play a role in the regulation of testosterone synthesis by the prepubertal testis.
The relationship between glycolysis, mitochondrial respiration, protein‐carboxyl methylation and motility in hamster epididymal spermatozoa
Authors: Fisher‐Fischbein Jocheved , Gagnon Claude , Bardin C. Wayne
Published: May 2008

Endogenous protein‐carboxyl methylase activity can be measured in intact motile spermatozoa by using [3H]methionine as a precursor of the methyl donor, S‐adenosylmethionine (SAM). Since the conversion of methionine to SAM requires ATP, the relationship between the energy metabolism of spermatozoa and methylation was investigated using inhibitors of glycolysis and mitochondrial respiration. When hamster spermatozoa from cauda epididymides were incubated in 12.2 mM glucose, glycolysis was progressively inhibited as concentrations of 2‐deoxyglucose (2‐DOG) increased. On the other hand, endogenous protein‐carboxyl methylation showed a biphasic response being stimulated at low concentrations of 2‐DOG and inhibited at higher concentrations. Sperm movement was also altered by 2‐DOG. Increasing concentrations of 2‐DOG in the incubation medium resulted in an increase in beat amplitude and a corresponding decrease in beat frequency. When the glucose concentration of the medium was reduced to 5 mM, protein methylation was inhibited at all concentrations of 2‐DOG. The biphasic effect of 2‐DOG on methylation at 12.2 mM and its monophasic effect at 5 mM suggested that this reaction was related to the effective glucose concentration. To investigate this possibility, endogenous protein‐carboxyl methylation was measured after incubation of sperm in glucose concentrations ranging from 0–48.8 mM. Low glucose concentrations stimulated protein methylation (up to 6.1 mM for maximal effect), but further increases in the glucose concentration***
Spontaneous improvement in semen quality: regression towards the mean
Authors: Baker H. W. G. , Kovacs G. T.
Published: May 2008

Regression towards the mean was demonstrated in semen analyses from 216 donors for artificial insemination by selecting those with low sperm concentration (< 40 times 106/ml), low motility (< 50%) or low motility index (< 120) in the first test. For each characteristic, the result was significantly higher in the second test, the means for first and second tests being, for sperm concentration 28 and 56 million per ml (n=14, P < 0.01), for motility 42 and 55% (n=14, P<0.01) and for the motility index 95 and 131 (n=24, P<0.001). Regression towards the mean occurs whenever extremes of the range of a variable and selected for re‐measurement. Many of the current treatments for oligospermia and asthenospermia have been promoted because semen quality improved during uncontrolled studies in which this phenomenon may have been operative. Using means of multiple samples before and following therapeutic intervention will not prevent regression towards the mean, only reduce its magnitude. Thus, placebos are essential in the evaluation of treatments for male infertility.
Postnatal differentiation of the enzymatic activity of the mouse epididymis
Authors: Abou‐Haila A. , Fain‐Maurel M. A.
Published: May 2008

Dehydrogenase and hydrolase activities were assessed histochemically during postnatal development of the mouse epididymis. At birth the activities of various enzymes were demonstrable along the epithelium at the same intensity. Variations occurred in the intensity of enzyme activities in principal cells, leading to regional differentiation which progressed according to an ascending pattern from the distal part (2nd week) to the medial and proximal parts (3rd week). The proximal part reached its definitive differentiation at the 4th week when the 5 segments characteristic of the adult state were distinguishable. At the same time, 3 types of “apical cells” (narrow, prominent and mitochondriagoblet cells) in the proximal part and “clear cells” in the medial and distal parts showed higher activity of several enzymes (dehydrogenases, acid phosphatase, Ca2+‐ATPase) than did adjacent principal cells. This histochemical data has led us to propose a model for epididymal cell differentiation in the mouse. The role of androgens in the development of those regional differences is discussed.
Dose and time related responses of the irradiated prepubertal rat testis
Authors: Delic J. I. , Hendry J. H. , Morris I. D. , Shalet S. M.
Published: May 2008

Dose‐related effects of radiation upon the seminiferous epithelium were examined in the prepubertal rat. Marked damage to the spermatogenic cell populations was produced by doses of 5 Gy and above. As a result serum levels of FSH were increased, maximum changes being observed at 2 weeks, but levels remaining high even at 36 weeks after irradiation. Serum levels of androgen binding protein (ABP) were inversely related to serum FSH. Above a threshold dose of 5 Gy, serum ABP levels were reduced to between 30–50% of control values, possibly indicating damage to the Sertoli cells. Progression in the degree of testicular failure was indicated at 36 weeks after a dose of 15 Gy by further increases in serum gonadotrophins when compared to earlier times and by the absence of spermatogenesis.
Long‐term safety of the oral androgen testosterone undecanoate
Authors: Gooren L. J. G.
Published: May 2008

In 35 men treated with testosterone undecanoate (TU) at a dosage of 80–200 mg/day, liver function was measured every 6 months for a period of 72 months. None of the parameters changed. In 8 subjects of 50–62 years of age upon starting this type of treatment, urine flow was not found to decrease over the test period of 72 months. Also other signs of benign prostatic hypertrophy were not reported. In 9 subjects for whom TU was the first type of androgen treatment, no signs of gynaecomastia were found during the first 6 months of the therapy or later. These data provide evidence that TU is a reasonably safe form of oral androgen therapy.
Electron microscopic evidence for deep invaginations of the lamina propria towards the seminiferous tubule lumen in a patient with varicocele
Authors: Haider S. G. , Passia D. , Servos G. , Hettwer H.
Published: May 2008

Ultrastructural studies on biopsy tissue from the right testis of a 39‐year old patient with varicocele revealed 2.5–5 μm thick invaginations of the lamina propria towards the lumen of the seminiferous tubules. These invaginations were of various lengths. The presence of invaginations was confirmed through examination of serial semi‐thin sections. In some seminiferous tubules two neighbouring deep invaginations were joined together thus completely encircling and thereby separating the basal compartment, and in some cases even the adluminal compartment, of the seminiferous tubule. The invaginations were surrounded continuously by the basement membrane and contained collagen fibres, cell processes of myoid cells and in some cases also their nuclei.
Seasonal changes in testicular structure and function in the blue fox (Alopex lagopus), as quantified by morphometric analysis and measurement of adenylate cyclase activity
Authors: Smith Adrian , Bugge Hans Petter , Berg Kjell Andersen , Møller Ordin , Hansson Vidar
Published: May 2008

The volume of the blue fox testis showed 5‐fold changes during the year, associated with considerable changes in cellular composition. The seminiferous epithelium was maximally regressed in August, when 94% of tubules contained only spermatogonia. By late October, approximately 6 months before the mating season, 40% of tubules contained primary spermatocytes. From the middle of January until the end of April all tubules contained spermatids or more advanced haploid cells. Tubular diameter increased by 73% during testicular re‐development, and epithelial height increased 3‐fold. Regression to the basal state occurred during May to July. The volume densities of the seminiferous epithelium and of interstitial tissue remained approximately constant throughout the year. Soluble Mn2+‐dependent adenylate cyclase activity showed seasonal variations that paralleled those of the haploid germ cell population and testicular volume, whereas somatic cell adenylate cyclase activity was relatively constant.
Age‐related effects of transection of the testicular blood vessels on subsequent testicular development in the pig
Authors: Noordhuizen‐Stassen E. N. , Wensing C. J. G.
Published: May 2008

Pigs of different ages were studied to assess the effect of age on the development of the testes after intra‐abdominal transection of the testicular artery and vein. Transection of the testicular artery and vein at different stages of sexual development had a variable effect on the growth and differentiation of the testes. Transection performed at a young age (2 months) had no effect on the development of the testes (previous study). The animals used in this study were between 3 and 12 months (adult) at the time of surgical intervention. Their testes appeared to be more sensitive to disturbance of the main blood supply. The alternative vascular pedicle (vasal artery) was unable to adapt sufficiently to the increased physiological requirements of the testis during development in more than 50% of the animals. The results obtained from adult males indicate that intra‐abdominal transection of the testicular vessels invariably has a deleterious effect on the testis.
Time‐ and temperature‐related alterations in seminal plasma constituents after ejaculation
Authors: Rui H. , Mørkås L. , Purvis K.
Published: May 2008

The effects of temperature and incubation time were examined on the concentrations of the following seminal plasma constituents in ejaculates from seven healthy volunteers: prostatic acid phosphate (PAP), citric acid, testosterone, prostaglandin E (PGE), fructose, protein, putrescine and the polyamines spermidine and spermine. The results indicated that the majority of glandular products were stable up to 3 h after ejaculation when stored at room temperature, with the exception of the prostatic diamine putrescine, which appeared to undergo rapid metabolism. Prolonged periods of incubation resulted in a gradual reduction in the levels of fructose and a significant increase in the activity of PAP and the levels of spermidine. On the basis of these findings it appears that an evaluation of the functional integrity of the accesory sex glands can be carried out on semen up to 3 h after ejaculation.
Stimulation of ornithine decarboxylase in the rat prostate by seminal plasma inhibin
Authors: Natraj U. , Vanage G. , Didolkar A. , Moodbidri S. B. , Sheth A. R.
Published: May 2008

The effect of seminal plasma inhibin on ornithine decarboxylase activity (ODC) in the rat prostate was studied. A single bolus injection of seminal plasma inhibin caused a 3‐ to 4‐fold increase in ODC activity within 2 h whereas testicular ODC was unchanged. The ODC response to seminal plasma inhibin was neutralized by specific antibodies generated against the inhibin preparation. Another peptide, thyroid releasing hormone has no effect on prostatic ODC activity, but it blocked the increase in enzyme activity induced by treatment with seminal plasma inhibin.
Increase in fluid viscosity during epididymal transit and the immobilization of rat epididymal spermatozoa
Authors: Eksittikul Thidarat , Chulavatnatol Montri
Published: May 2008

A microcapillary method was developed to measure the viscosity of small volumes of undiluted epididymal fluid. Fluid from the cauda epididymis registered 82 ± 17 centipoise which was much more viscous than fluid from the caput region (8 ± 2 centipoise). Initiation of sperm motility was strongly suppressed in the viscosity range of 7 to 150 centipoise. A significant increase in the viscosity of fluid from the caput region was observed when immobilin in the fluid binds with a lectin from Jack fruit (Artocarpus heterophyllus). Thus, it is postulated that aggregation of the immobilin induced by a lectin‐like material produced by the cauda epididymis may be a mechanism by which fluid viscosity is increased during epididymal transit.
Exposure to ethanol during capacitation impairs the fertilizing ability of human spermatozoa in vitro
Authors: Salonen I.
Published: May 2008

To validate earlier findings, mainly in laboratory animals, the effect of ethanol on the fertilizing ability of human spermatozoa has been investigated. Ethanol added to the capacitation medium reduced the penetration of zona‐free hamster eggs by human spermatozoa in a dose‐dependent manner at concentrations from 50 to 500 mg % (0.05–0.5%). Fertilizing capacity was at least partially restored by washing in ethanol‐free medium. Ethanol exposure before capacitation had a slight stimulatory effect on the penetration of spermatozoa into zona‐free hamster ova. The motility of spermatozoa was not altered significantly, either quantitatively or qualitatively, by the presence of ethanol in the capacitation medium. These results suggest that the decrease in fertilizing ability of spermatozoa induced by ethanol during capacitation is due to a specific action on the capacitation process.
Regulation of interstitial cell function by seminiferous tubules in intact and cryptorchid rats
Authors: Syed Viqar , Karpe Bengt , Plöen Leif , Ritéen E. Martin
Published: May 2008

The effects of experimental cryptorchidism on seminiferous tubule secretions and interstitial cell testosterone production were studied in vitro. Spent media obtained from incubations of seminiferous tubules (SMST) from cryptorchid rats caused a significant increase in testosterone production when added to interstitial cells isolated from intact rats. The previously noticed inhibitory activity of the SMST from stages VIII–XI of the sperma‐togenic epithelial cycle gradually disappeared after the induction of experimental cryptorchidism. SMST obtained from both sham‐operated or cryptorchid rats stimulated basal testosterone production when added to interstitial cells from cryptrochid rats. SMST from rats had been cryptorchid for 7, 14 and 28 days stimulated testosterone production when added to interstitial cells prepared from intact animals. Seminiferous tubules from cryptorchid rats therefore appear to be the source of a heat stable, trypsin‐resistant factor with an apparent molecular weight of between 5000 and 10 000 daltons which stimulates testosterone production when added to interstitial cells in vitro. Its activity could not be blocked by an LRH antagonist. This factor enhances both basal and LH‐stimulated secretion of testosterone in contrast to the inhibitory activity which involves only a partial blockade of LH‐dependent steroidogenesis.
Grouping of human ejaculates according to the degree of coagulation and the relationship to the levels of choline and cholinesterase
Authors: Mandal Arabinda , Bhattacharyya Asok K.
Published: May 2008

Human ejaculates were divided into 3 groups (I, II and III) according to the extent of their coagulation and the levels of free choline and cholinesterase were determined together with seminal vesicular N‐acetylamino sugar and prostatic (zinc) marker components. Coagulation was determined as the percent coagulum (CG) at 5 min after ejaculation. The mean (± SEM) values for CG at 5 min in groups I, II and III were 6 ± 2, 43 ± 4 and 79 ± 2, respectively. The time for 100% liquefaction in the 3 groups were 4.7 ± 0.8, 12.9 ± 1.4 and 19.1 ± 2.1 min, respectively. Group III had significantly higher levels of choline and cholinesterase activity than groups I and II. The choline level was correlated significantly (r = 0.58) with the concentration of N‐acetylamino sugar, but there was no correlation with the level of zinc. Evaluation of the level of choline in prostatic fluid, in semen from azoospermic men and in ejaculates with different CG values suggested that the level of choline may provide valuable information about activity of the seminal vesicles. Release of choline in group I was only 33 and 50% of that groups III and II, respectively. 60% of the total release of choline occurred during the liquefaction phase. The mean activity of cholinesterase in the prostate was only 27% lower than that found in seminal plasma. The liquefaction time and the concentration of choline, N‐acetylamino sugar and zinc decreased significantly in ejaculates after 2 days of abstinence.
Identification of the uterine factor(s) which induce the acrosome reaction in buffalo (Bubalus bubalis) spermatozoa
Authors: Sidhu K. S. , Bassi A. , Gupta B. C. , Guraya S. S.
Published: May 2008

This study characterizes factors present in uterine fluid from oestrous buffalos which induce the acrosome reaction in buffalo spermatozoa. Characterization was performed by dialysis, heat treatment (90°C, 30 min) and deproteinization of uterine fluid. The % motility and viability of sperm was maintained better in unfractionated uterine fluid than in dialysed fluid. Heating and deproteinization of the dialysed uterine fluid significantly reduced the % motility and viability of sperm. The percentage of sperm showing different stages of the acrosome reaction (swelling, and vesiculation) was significantly higher for sperm incubated in dialysed than in neat uterine fluid. There was no significant difference in the % of sperm showing acrosome shedding in both dialysed and neat uterine fluid. Heat treatment destroyed the ability of uterine fluid to induce the acrosome reaction. Sperm incubated in the protein precipitate from uterine fluid showed all stages of the acrosome reaction. Thus, the uterine factor(s) responsible for inducing the acrosome reaction in buffalo sperm was associated with the non‐dialysable, albumin‐like protein fraction and was heat‐labile.
Flow cytometry derived DNA content of the primary lesions of advanced germ cell tumours
Authors: SLEDGE G. W. , EBLE J. N. , ROTH B. J. , WUHRMAN B. P. , EINHORN L. H.
Published: May 2008

We currently lack good prognostic indicators for patients with advanced disseminated germ cell tumours (GCT). An analysis of archival tumour samples of forty‐nine patients with advanced GCT for flow cytometry derived DNA content suggests an inverse relationship between tumour proliferative activity and patient survival. The great majority of patients with advanced GCT have aneuploid tumour subpopulations. This analysis suggests that the survival of patients with advanced GCT may depend in part on kinetic variables present in the primary tumour.
Proliferation of human testicular tumours
Authors: RABES H. M.
Published: May 2008

Whole tumour perfusion with radioactive DNA precursors reveals that proliferation of human testicular tumours differs widely depending on type and stage of development. In seminomas a homogeneous distribution of proliferating cells at early stages is followed by a shift of the growth fraction to the periphery at advanced stage. Embryonal carcinomas show a chessboard‐like pattern of proliferating fractions with high 3H‐thymidine labelling indices and short tpot. In mature teratomas proliferation is low. It increases in immature teratocarcinomas. Lack of proliferation is observed in β‐hCG‐positive syncytiotrophoblastic cells of choriocarcinomas, the growth fraction being limited to the cytotrophoblastic compartment.