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PubMed1975

Stimulation of ejaculated human spermatozoa by caffeine.

Caffeine (1, 3, 7-trimethyl-2, 6-dioxypurine), a cyclic nucleotide phosphodiesterase inhibitor, increased the motility of ejaculated human spermatozoa. Both the percent motility and the grade of forward progression were significantly increased (P smaller than 0.001) and maintained in the presence of 6 mM of caffeine for up to five hours at 37 C. Increases in percent motility greater than two-fold occurred among the groups having low initial motility. Increases in samples with a high initial percent motility (greater than 60%) were not as dramatic, but they were still significant. In addition, the grade of motility or forward progression was increased in all groups up to one full unit. The longevity of the spermatozoa, judged by activity, was also increased for up to five hours.

Caffeine↗
PubMed1982

Effects of purification or split ejaculation of semen and stimulation of spermatozoa by caffeine on their motility and fertilizing ability with the use of zona-free hamster ova.

Purification of semen with Sephadex G-50 medium powder or bovine serum albumin (BSA) (20% in medium) columns increases the percentage of motility. Spermatozoa that passed a BSA column or a Sephadex column have significantly higher velocity than unmanipulated spermatozoa. Caffeine (7 mM) stimulation did not show any effect on motility. Neither purification procedures nor stimulation with caffeine improved the in vitro fertilization capacity of capacitated spermatozoa, as determined by interaction with zona-free hamster ova. No difference in in vitro fertilizing capacity could be demonstrated between the first and the last fractions of split ejaculates. After grouping the fractions according to sperm counts, fractions with higher total (motile) sperm counts, and fractions with higher sperm counts had significantly higher fertilization percentages than the fractions with lower (motile) sperm counts.

Animals↗
PubMed1983

Assessment of a new spermicidal agent against ejaculated dog and human spermatozoa in vitro.

The spermatostatic potencies of a new vaginal contraceptive agent, RS-37367, and a standard surfactant compound, nonoxynol-9, have been compared by using ejaculated dog and human spermatozoa. RS-37367 was 25 to 50 times more potent than nonoxynol-9 against dog spermatozoa. Nonparallel concentration-response lines were obtained against human spermatozoa. Concentrations of RS-37367 causing immediate spermatostasis against dog spermatozoa resulted in vesiculation of the plasma and outer acrosomal membranes of spermatozoa; similarly, immediately spermatostatic concentrations of nonoxynol-9 were associated with the previously documented generalized membrane stripping. The activities of both RS-37367 and nonoxynol-9 were affected by the concentration of dog spermatozoa in semen-compound mixtures. Short-term (5-minute) exposure of spermatozoa to concentrations of RS-37367 not immediately spermatostatic resulted in progressive immobilization of spermatozoa. Extensive washing of the spermatozoa was not able to reverse this effect, in contrast to spermatozoa transiently exposed to nonoxynol-9.

Animals↗
PubMed1987

Concentration of pefloxacine in split ejaculates of patients with chronic male accessory gland infection.

The concentrations of pefloxacine and its N-demethylated derivative were measured in split ejaculates of 12 patients with chronic male accessory gland infection during treatment with 400 mg. pefloxacine twice a day. The mean concentrations of pefloxacine and N-demethylated pefloxacine (mg. per l.) were 8.7 +/- 1.2 (standard error of the mean) and 4.2 +/- 0.7 in fraction 1, and 9.8 +/- 1.1 and 4.3 +/- 0.6 in fraction 2. The concentrations in both fractions were correlated strongly (r equals 0.97). The concentration of pefloxacine in the secretory fluids of the prostate and seminal vesicles are 30-fold the minimal inhibitory concentration 90 of Escherichia coli and Klebsiella species, 100-fold the minimal inhibitory concentration 90 of Proteus mirabilis and equal to the minimal inhibitory concentration 90 of Streptococcus faecalis. In three-fourths of the patients signs of infection resolved after 4 weeks of treatment.

Adult↗
PubMed2001

Effects of glucose and fructose on motility patterns of dog spermatozoa from fresh ejaculates.

This study was performed to gain insight about how fructose and glucose modulate dog spermatozoa motility in the absence of other motility-modulating factors. Incubation of dog spermatozoa from fresh ejaculates in a basal medium without sugars for 60 min at 37 degrees C induced a progressive decrease in the percentage of motile spermatozoa and in some mean motility parameters, such as mean velocity (VAP), linear coefficient (LIN) and dance (DNC), and an increase in the mean frequency of head displacement (BCF). This indicates a progressive loss of linearity and an increase in oscillatory movement. Addition of 10 mM fructose prevented these effects. Incubation in a basal medium with 10 mM glucose for 60 min at 37 degrees C provoked a fast and intense decrease of LIN and a slight increase of DNC, inducing a less linear and more oscillatory mean movement. Neither fructose nor glucose modified the percentage of motile spermatozoa. The response to both sugars was dose-dependent, with differences appearing at concentrations as low as 1 mM. An analysis of the spermatozoa subpopulation placed above the 95th percentile of the whole population and a factorial analysis of the data indicated that the changes in the mean values of the motility parameters were mainly due to a specific motile subpopulation that had a strong reaction to the two sugars. Our results indicate that fructose, at concentrations from 1 to 10 mM, induced a more linear and less oscillatory motility pattern than glucose. Moreover, from our results we suggest the presence of motile dog sperm subpopulations with an increased sensitivity to fructose and glucose.

Animals↗
PubMed2003

Seasonal timing of sperm production in roe deer: interrelationship among changes in ejaculate parameters, morphology and function of testis and accessory glands.

Roe deer are seasonal breeders with a short rutting season from mid-July to mid-August. The seasonality of reproductive activity in males is associated with cyclic changes between growth and involution of both testes and the accessory sex glands. This study characterizes morphological and functional parameters of these organs prior to, during and after breeding season in live adult roe deer bucks. Size and morphology of the reproductive tract was monitored monthly by transcutaneous (testes, epididymis) and transrectal (accessory glands) ultrasonography. Semen was collected by electroejaculation. Concentration, motility and morphological integrity of spermatozoa as well as the content of proteins and testosterone in semen plasma were evaluated. Proportions of haploid, diploid and tetraploid cells were estimated by flow cytometry in testicular tissue biopsies. Serum testosterone was measured by enzyme immunoassay. Most parts of the male reproductive tract showed distinct circannual changes in size and texture. These changes were most pronounced in the testes, seminal vesicles, and prostate. All reproductive organs were highly developed during the rut only. The volume of ejaculates, total sperm number and percentages of motile and intact spermatozoa also showed a maximum during this period and corresponded with high proportions of haploid cells in the testis. The highest percentages of tetraploid cells were found in the prerutting period. The production of motile and intact spermatozoa correlated with both the protein content of semen plasma and the concentration of testosterone in semen plasma and blood serum. These results suggest the importance of combined actions of the testes and accessory sex glands and the crucial role of testosterone in facilitating the optimal timing of intensified semen production to ensure sufficient numbers of normal spermatozoa in seasonal breeders.

Animals↗
PubMed2001

Free radical generation in ejaculate samples from infertile patients.

Generation of free radicals in ejaculate samples from infertile patients was evaluated using chemiluminescent technique. The presence of antisperm antibodies in samples increased the possibility of damages to spermatozoon plasma membranes due to excessive generation of free radicals.

Antibodies↗
PubMedDate not supplied

Dapoxetine, a novel treatment for premature ejaculation, does not have pharmacokinetic interactions with phosphodiesterase-5 inhibitors.

Potential pharmacokinetic interactions between dapoxetine, a serotonin transporter inhibitor developed for the treatment of premature ejaculation (PE), and the phosphodiesterase-5 inhibitors tadalafil and sildenafil, agents used in the treatment of erectile dysfunction (ED), were investigated in an open-label, randomized, crossover study (n=24 men) comparing dapoxetine 60 mg, dapoxetine 60 mg+tadalafil 20 mg, and dapoxetine 60 mg+sildenafil 100 mg. Plasma concentrations of dapoxetine, tadalafil, and sildenafil were determined by liquid chromatography-tandem mass spectrometry. Tadalafil did not affect the pharmacokinetics of dapoxetine, whereas sildenafil increased the dapoxetine AUCinf by 22%; these effects were deemed not clinically important. Dapoxetine did not appear to affect the pharmacokinetics of tadalafil or sildenafil. Most adverse events were mild in nature. Thus, dapoxetine has no clinically important pharmacokinetic interactions with tadalafil or sildenafil, and the combinations are well tolerated.

Adolescent↗
PubMed1998

Characterization of mouse epididymal acrosin: comparative studies with acrosin from boar and human ejaculated spermatozoa.

Acrosin is an acrosomal protease believed to play a major role in fertilization. It is synthesized as an inactive precursor, proacrosin, which is processed via (auto)proteolysis into active form(s). In this paper, comparative studies on the characteristics of acrosin from mouse, boar and human are reported. The mouse proacrosin/acrosin was especially investigated to clarify whether or not the enzyme undergoes modifications during epididymal maturation. Acrosomal extracts from mature and immature mouse spermatozoa, as well as from ejaculated boar and human spermatozoa, were analysed by means of SDS-electrophoresis, Western blot and activity measurements. The studies showed that epididymal maturation produced a shift in the molecular weight of proacrosin. It was also observed that the activation kinetics differ strongly between the three species studied. Human proacrosin showed a constant substrate turnover, acrosin from boar showed sigmoidal activation kinetics and mouse acrosin, either from the caput or the cauda epididymides, showed a rapid decay in activity, suggesting the presence of an endogenous specific inhibitor.

Acrosin↗
PubMed1998

Effects of calcium and bicarbonate on head-to-head agglutination in ejaculated boar spermatozoa.

The present study was conducted to reveal the effects of calcium and bicarbonate on the occurrence of head-to-head agglutination in ejaculated boar spermatozoa in vitro. Boar spermatozoa were washed and incubated in a modified Krebs-Ringer bicarbonate (mKRB) in a 37 degrees C CO2 incubator (5% CO2 in air) for 1-5 h. Before and after the incubation, aliquots of each sperm sample were fixed, smeared on glass slides, and stained with a phosphate-buffered solution of Giemsa to assess the percentages of head-to-head agglutinated spermatozoa. Before the incubation, only 5-12% of the spermatozoa were agglutinated. After the 1-h incubation, however, the percentage of head-to-head agglutinated spermatozoa rose to approximately 50%, followed by only minor increases thereafter. This rise was dependent on the concentrations of calcium chloride contained in the mKRB and was attenuated by the addition of 2 mM [ethylenebis(oxyethylenenitrilo)]tetra-acetic acid (EGTA) to the medium. Moreover, the replacement of sodium bicarbonate with 2-[4-(2-hydroxyethyl)-1-piperazinyl]ethanesulfonic acid (Hepes) in the medium and treatment with ruthenium red, which have both been shown previously to inhibit calcium uptake by boar spermatozoa, significantly reduced the rise. Based on these findings, it was concluded that extracellular calcium and bicarbonate are key factors regulating head-to-head agglutination in boar spermatozoa. The possible relationship between agglutinability and the fertilizing ability of boar spermatozoa is also discussed.

Animals↗
PubMed1986

The "G spot" and "female ejaculation": a current appraisal.

In the light of the available evidence, this paper reviews two current controversial issues in the area of female sexuality: the "G spot" and "female ejaculation." It is concluded that evidence in support of the "G spot"--defined as a discrete anatomical structure located on the anterior vaginal wall, which swells upon being tactilely stimulated--is inconclusive, and, in the event of its existence, no evidence has been produced linking it to Skene's glands. However, it seems reasonable to accept that women possess a zone of tactile erotic sensitivity on the anterior vaginal wall, which in many of them may extend to the entire anterior wall and to the posterior vaginal wall. It also seems that some women emit a fluid through the urethra at orgasm, although its true nature and anatomical origin are still unclear.

Exocrine Glands↗
PubMed1989

The role of the Grafenberg Spot and female ejaculation in the female orgasmic response: an empirical analysis.

Despite earlier contrary claims, researchers have found evidence that a sensitive area (Grafenberg Spot) exists in the vaginal barrel. This area is a potential source of orgasm independent of clitoral stimulation. Other researchers have reported that some women experience a sudden spurt of fluid at the moment of orgasm. In the interest of contributing to further understanding of physiological and psychological sexual satisfaction, and alleviation of concerns about perceived urination during orgasm, the investigators explored a series of variables thought to be associated with perceptions of the Grafenberg Spot and its relationship, if any, to the female orgasmic response and female ejaculation. An anonymous questionnaire was distributed to 2,350 women in the United States and Canada, with a subsequent 55% return rate. A number of factors were found to be associated with perceived existence of a sensitive area in the vaginal barrel which, when properly stimulated, activates orgasm. Women who reported sensitive area orgasms were also more likely to report a spurt of fluid at moment of orgasm.

Body Fluids↗
PubMedDate not supplied

A simple technique for the purification of plasma membranes from ejaculated boar spermatozoa.

Spermatozoa were initially separated from fresh boar ejaculates using a 1.0 M sucrose density gradient. Spermatozoa (1 x 10(8) cells/ml) were subjected to gas cavitation (650 psi, 10 minutes), followed by a 4-step centrifugation technique to yield the final plasma membrane preparation. Purity of the plasma membrane isolate was determined using microscopic techniques (i.e. differential interference contrast and transmission electron microscopy) and marker enzymes for biochemical characterization. Plasma membranes were found to be removed primarily from the periacrosomal region of the sperm. Acrosomes appeared to remain intact on the cavitated spermatozoa. Transmission electron microscopy yielded a homogenous population of 100-200 microns unilamellar vesicles. Enzyme markers specific for plasma, acrosome and mitochondrial membranes substantial the purity observed under visual examination.

5'-Nucleotidase↗
PubMed1986

Purification and characterization of two plasma membrane domains from ejaculated bull spermatozoa.

Plasma membranes were detached from ejaculated bull spermatozoa by a brief sonication in a moderately hypotonic medium, and the released plasma membranes were partially purified by differential centrifugation. The resulting fraction was enriched 8- and 15-fold in alkaline phosphatase and 5' nucleotidase activities, respectively, compared with the starting sonicated spermatozoa. This total plasma membrane fraction was separated into two distinct fractions by equilibrium density centrifugation on a continuous linear sucrose gradient. Two peaks of light scattering material were formed at densities of 1.117 and 1.148 g/ml. The denser peak contained most of the protein of the plasma membrane fraction, whereas nearly all the concanavalin A binding activity was found in the lighter peak. The two bands had distinctly different polypeptide compositions when analyzed by SDS PAGE. Polyclonal antibodies were raised in rabbits against a major integral membrane glycoprotein of each fraction (Mr of 92,000 in the light peak and 98,000 in the dense peak). The two antigens were detected on the surface of intact spermatozoa by indirect immunofluorescence microscopy. The 92-kD protein (present in the lighter band) was detected only on the plasma membrane of the acrosomal and anterior postacrosomal regions of the head. The 98-kD antigen, present in the heavier band, was localized to the surface of the postacrosomal region of the head, to the principal piece of the tail, and to the connecting piece between the head and tail. The exclusive localization of the 92-kD polypeptide to the surface of the anterior portion of the head was confirmed by immunoelectron microscopy. These data show that the two fractions isolated on the sucrose gradient originate from different regions of the sperm cell plasma membrane.

Animals↗
PubMed1984

Sensitivity of picroindigocarmine/nuclear fast red (PIC/NF) stain for detection of spermatozoa: a serial dilution study of human ejaculate.

A serial dilution study from human ejaculate was done in order to assess the sensitivity of a commonly employed stain, picroindigocarmine/nuclear fast red, for the detection of spermatozoa. The results of the study indicate that spermatozoa may be detected readily at very low concentrations by scanning 20 high-power fields of a stained smear.

Female↗
PubMed1998

Influence of oxygen tension on function of isolated spermatozoa from ejaculates of oligozoospermic patients and normozoospermic fertile donors.

Oxygen radical generation is known to be detrimental to sperm function. An example of a reactive oxygen species-associated male pathology is oligozoospermia in which fertilization and pregnancy rates are low in in-vitro fertilization (IVF) programmes. As the extent of the modifications induced by reactive oxygen species (ROS) depends on several factors, notably from oxygen tension in the incubation medium, the aim of this study was to examine the influence of a low (5%) rather than atmospheric (20%) oxygen tension in the incubator gas phase on the function of Percoll-selected spermatozoa from ejaculates of oligozoospermic patients and normozoospermic fertile donors. After incubation for several hours in a gas phase of either 5% CO2/90% N2/5% O2 or 5% CO2/95% air (20% O2), none of the parameters investigated, e.g. movement characteristics, potential of spermatozoa to acquire hyperactivated motility, to undergo the acrosome reaction when challenged with a calcium ionophore and to fuse with zona-free hamster oocytes, was significantly different between the two oxygen tensions in fertile donors. In contrast, among oligozoospermic patients, the motility parameters, the percentage of hyperactivated motility and of induced-acrosome reaction were significantly improved under a gas phase of 5% O2 compared with those observed under an atmosphere of 20% O2 (P < 0.05). Exposure to 5% rather than 20% oxygen tension also induced a significant increase in the percentage of penetration of zona-free hamster eggs after capacitation for 17 h, but no difference was found in the mean number of bound spermatozoa per oocyte. After incubation for 24 h, a significantly higher survival rate was observed under 5% compared with 20% oxygen tension. These results show that the use of a low oxygen tension rather than air might improve spermatozoan competence of oligozoospermic patients during IVF programmes.

Acrosome Reaction↗
PubMed1998

Ultrastructural localization of angiotensin-converting enzyme in ejaculated human spermatozoa.

Angiotensin-converting enzyme (ACE) is known to be released from human spermatozoa during capacitation. However, it has not yet been localized ultrastructurally in ejaculated sperm cells. Therefore, the purpose of the present study was to demonstrate the location of ACE by means of immunoelectron microscopy and direct immunofluorescence. In addition, ACE activity of spermatozoa was correlated with standard semen parameters. The activity of angiotensin-converting enzyme was measured in spermatozoa from 115 donors and patients attending the andrological outpatient department. Progressive motility was negatively correlated with sperm ACE activity (Spearman rank correlation r=-0.364, P < 0.0001), whereas no statistically significant correlations with sperm concentration, total motility and morphology were observed. Immunoelectron microscopy demonstrated that ACE is mainly located at the plasma membrane of the acrosomal region, equatorial segment, postacrosomal region and midpiece. In contrast, only weak ACE-like immunoreactivity was found at the flagellum. In cases of cells with missing plasma membranes ACE seems also to be located at the surface of the outer acrosomal membrane. By means of immunohistochemical methods, different patterns of ACE-like immunofluorescence were observed: (i) fluorescence of the acrosome or the entire sperm head, midpiece and flagellum; (ii) fluorescence of the postacrosomal region, midpiece and flagellum; (iii) bright fluorescence of the equatorial segment with less intensive labelling of the postacrosomal region and flagellum. Induction of the acrosome reaction by calcium ionophore A23187 resulted in an increase of spermatozoa with weak acrosomal fluorescence, indicating loss of the plasma membrane.

Acrosome↗
PubMed1994

Morphometric characteristics of motile spermatozoa in subfertile men with an excess of non-sperm cells in the ejaculate.

A comparison has been made between the morphological dimensions of motile spermatozoa in subfertile men demonstrating a persistent excess of non-sperm cells in their semen and those found in spermatozoa from fertile controls. Scanning electron microscopy and image analysis were used to make a morphometric assessment of defined sperm parameters in the study and control subjects. Half of the study cohort had an excess (> 5 x 10(6)/ml) of seminal leukocytes and the remainder an excess of sperm precursors in the ejaculate. In subjects with a sperm precursor excess, the motile spermatozoa had several significantly larger head parameters than those from both the fertile controls and those men with a leukocyte excess. Mid-piece and tail measurements did not differ significantly between groups. These findings suggest that, where there are large numbers of immature germinal elements present in semen, there is aberrant morphological development of the motile, apparently mature, spermatozoa which may represent disordered spermatogenesis.

Female↗