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PubMed1997

Transbilayer motion of spin-labelled phospholipids in the plasma membrane of epididymal and ejaculated ram spermatozoa.

The transbilayer movement and distribution of spin-labelled phospholipid analogues were studied in the plasma membrane of ram sperm cells isolated from functionally different regions of the epididymis (caput, cauda) and from the ejaculate. As already shown for ejaculated cells, (i) a rapid movement of aminophospholipid analogues phosphatidylserine and phosphatidylethanolamine from the exoplasmic to the cytoplasmic leaflet, and (ii) a slow transbilayer movement of phosphatidylcholine were observed in the plasma membrane of maturating ram sperm cells. This suggests an asymmetric steady state transbilayer distribution of phospholipids, with a preferential enrichment of aminophospholipids on the cytoplasmic leaflet of those cells. The fast inward redistribution of the aminophospholipid analogues is consistent with the presence of an aminophospholipid translocase activity in all three sperm cell preparations. The translocase activity was enhanced slightly during the epididymal transit of spermatozoa. However, compared with epididymal sperm cells, a marked increase in the aminophospholipid translocase activity and a more pronounced phospholipid asymmetry for phosphatidylethanolamine was established for ejaculated spermatozoa. The physiological relevance of the rapid removal of aminophospholipids from the exoplasmic leaflet of the plasma membrane of ram sperm cells is discussed. The quality of sperm cell fractions was characterized by the cell morphology, membrane integrity and the cellular ATP concentration.

Adenosine Triphosphate↗
PubMed1999

Origin of DNA damage in ejaculated human spermatozoa.

The molecular basis of many forms of male infertility is poorly defined. One area of research that has been studied intensely is the integrity of the DNA in the nucleus of mature ejaculated spermatozoa. It has been shown that, in men with abnormal sperm parameters, the DNA is more likely to possess strand breaks. However, how and why this DNA damage originates in certain males and how it may influence the genetic project of a mature spermatozoon is unknown. Two theories have been proposed to describe the origin of this DNA damage in mature spermatozoa. The first arises from studies performed in animal models and is linked to the unique manner in which mammalian sperm chromatin is packaged, while the second attributes the nuclear DNA damage in mature spermatozoa to apoptosis. One of the factors implicated in sperm apoptosis is the cell surface protein, Fas. In this review, we discuss the possible origins of DNA damage in ejaculated human spermatozoa, how these spermatozoa arrive in the ejaculate of some men, and what consequences they may have if they succeed in their genetic project.

Animals↗
PubMed1991

p-Chloroamphetamine-induced ejaculation and the 22-kHz vocalization of the male rat.

It is well known that the male rats paired with receptive females emit the 22-kHz vocalization after ejaculation. The question addressed is whether after ejaculation injected with PCA without receptive females the 22-kHz call would be emitted. Emission of the 22-kHz call in males injected by PCA was not observed after ejaculation.

Animals↗
PubMed1993

Effects of p-chloroamphetamine (PCA) on ejaculation in aged rats.

In general, sexual activity in normal animals declines with increasing age. In aged male rats, for example, no ejaculation occurs when paired with receptive females. The ejaculatory response induced by p-chloroamphetamine (PCA) in aged adult rats, 14 to 18 months of age, was observed. The animals were treated intraperitoneally with PCA. The ejaculation rates were 0.28.6, 57.1 and 100% at doses of 0.3125, 0.625, 1.25 and 2.5 mg/kg, respectively. These animals, with a few exceptions, showed an ejaculation within 2 hrs of PCA injection. These data for aged adults are similar to those for young adults.

Aging↗
PubMed2006

Low expression of glycoprotein subunit 130 in ejaculated spermatozoa from asthenozoospermic men.

Previous studies showed that interleukin-6 (IL-6) was expressed in human Leydig and Sertoli cells and that it inhibited sperm motility. The aim of this study was to compare the expression of IL-6, IL-6R, and GP130 in ejaculated spermatozoa between normozoospermic and asthenozoospermic men. Human spermatozoa in the semen were purified by Percoll gradient technique to separate the seminal plasma and other round cells. RT-PCR, immunocytochemistry, and Western blot were used to detect the expression of IL-6, IL-6R, and GP130 in spermatozoa. With RT-PCR, only GP130 mRNA but not IL-6 and IL-6R mRNA was expressed in human ejaculated spermatozoa. The expression of GP130 mRNA was significantly lower in asthenozoospermic men than in normozoospermic men. The protein expression of GP130 was further confirmed by both immunocytochemistry and Western blot. Again, GP130 protein levels were significantly lower in asthenozoospermic men than in normozoospermic men. The results suggested that the decreased expression of GP130 in ejaculated spermatozoa could be associated with low sperm motility in asthenozoospermic men.

Blotting, Western↗
PubMed2004

Phosphodiesterase 5 inhibitors in rapid ejaculation: potential use and possible mechanisms of action.

Rapid (premature) ejaculation (RE) is a very common sexual disorder. This condition may be primary or secondary to underlying disease. Control of RE has been primarily focused on behavioural therapy, topical anaesthetics, tricyclic antidepressants and selective serotonin reuptake inhibitors; however, an approved treatment does not exist. Recently, a number of clinical trials have studied the potential effectiveness of the phosphodiesterase (PDE)-5 inhibitor sildenafil in the treatment of RE. Results of most of these studies have been encouraging. Available data indicate that there is clinical, anatomical, physiological, pharmacological and genetic evidence to explain the efficacy of PDE5 inhibitors in RE. The rationale for the use of PDE5 inhibitors in the treatment of RE could be due to possible peripheral and central mechanisms. Possible peripheral ejaculation retarding capabilities may include modulation of the contractile response of the vas deferens (VD), seminal vesicles (SV), prostate and urethra, induction of a state of peripheral analgesia, and prolongation of the total duration of erection. Possible central mechanisms may involve lessening of the central sympathetic output. Furthermore, there is evidence from knockout mice to explain the efficacy of PDE5 inhibitors in RE. Mice lacking the gene for endothelial nitric oxide synthase develop a condition similar to RE. On the other hand, mice lacking the gene for heme oxygenase-2 develop a condition similar to delayed ejaculation. This review also discusses the findings against the use of these agents in RE. In conclusion, a review of the literature suggests the potential usefulness of PDE5 inhibitors as a promising line of therapy in RE but further studies are needed.

Animals↗
PubMed2000

Prostate vascular flow: the effect of ejaculation as revealed on transrectal power Doppler sonography.

OBJECTIVE: The objective of our study was to determine the effect of ejaculation on prostate vascular flow. SUBJECTS AND METHODS: Using power Doppler technology, we performed four transrectal sonographic examinations before and immediately, 6 hr, and 24 hr after ejaculation in 10 healthy volunteers. Images were assessed by three independent observers. RESULTS: Ninety-seven percent of the images ranked as having the least flow were from the baseline examination. There was a significant difference between the rankings when categorized into the four time sets (mean score for the baseline group was 1.1, whereas for the immediate, 6-, and 24-hr postejaculation groups it was 2.5, 2.9, and 2.4, respectively (p<0.0001). The only statistically significant difference was between the baseline and the three remaining groups. Interobserver agreement was high, with the chance-corrected measure of agreement of 0.78. CONCLUSION: Transrectal sonography revealed that prostate vascular flow increases dramatically after ejaculation and remains elevated for at least 24 hr. This observation should be considered when power Doppler sonography is used to assess for potential hyperemia in patients suspected of having prostate abnormalities.

Adult↗
PubMed1986

Fine structure of spermatozoa retrieved from retrograde ejaculates.

The proportion of viable, motile spermatozoa retrieved from retrograde ejaculates has been consistently low. Electron microscopic studies of spermatozoa of retrograde ejaculates collected in Baker's buffer and washed in Ham's F10 medium supplemented with 2% human serum albumin revealed considerable ultrastructural lesions to the sperm head and the midpiece. Swelling and/or loss of plasma membrane was observed in most of the sperm. In others, the membrane continuity was disrupted, and tattered remnants of it remained attached to a grossly abnormal acrosome. The acrosomal cap in the majority of the spermatozoa was swollen and irregular in shape. Some of the spermatozoa lacked the acrosome, and the sperm heads of these were lined by the inner acrosomal membrane. Subcellular derangement in the midpiece of retrograde spermatozoa was characterized by mitochondrial swelling and lysis, indicating definite cytotoxic injury to the spermatozoa. These EM observations are consistent with the findings of high sperm wastage in semen from men with retrograde ejaculation.

Adult↗
PubMed1986

Characterization of rabbit sperm by equilibrium sedimentation in Percoll during frequent ejaculation.

Qualitative and quantitative changes of rabbit sperm were observed during frequent ejaculation. Semen volume, sperm concentration, percentage of motility, and fertility index of Farris (FI) decreased with frequent ejaculation, and these values recovered to initial levels after a 24-day abstinence period. A remarkable change was found in the sperm distribution profile in Percoll density gradients after equilibrium sedimentation. The main peak of sperm was shifted from fraction number 4 on the first day of ejaculation to number 7 on the fifth day. Fraction numbers 1-4 showed a high percentage of motility, whereas the sperm motility from fraction numbers 7-10 was quite low. Motile and morphologically mature sperm had higher apparent density than immotile or immature sperm. This suggests that rabbit sperm motility might be related to the apparent density of the sperm cell.

Animals↗
PubMed1990

Improved motility of retrograde ejaculates by adding donor seminal plasma.

Poor quality sperm motility might, in some instances, be related to a defect in the seminal fluid rather than in an intrinsic sperm defect. Three men with sperm lacking progressive forward motion (PFM), 40 min after suspension of their small antegrade fraction of a retrograde ejaculation in Ham's F-10 medium, did demonstrate sperm with PFM after suspension of the sperm in donor seminal plasma (DSP). All three achieved pregnancies following the intracervical insemination of their wives within a total of nine ovulatory cycles. Further investigation is needed to determine if the use of DSP can be applied to improve sperm motility in infertile males with a asthenozoospermia but without the complications of retrograde ejaculation. Suspension of sperm in donor seminal plasma had an enhanced effect on asthenozoospermia compared to Ham's F-10 medium in three infertile males with retrograde ejaculation and enabled them to impregnate their wives.

Ejaculation↗
PubMedDate not supplied

Effect of time interval between ejaculations on semen parameters.

The suggested abstinence period prior to performing a semen analysis has been 2-5 days. If one allows too long of an interval between ejaculates, motility will decrease significantly. This study was designed to evaluate whether any of the semen parameters change with increasing intervals of time between ejaculates and, if so, what parameters are involved. A derived calculation total-live sperm count (product of count/milliliter x volume x percent motility) was significantly lower at 3 days than at 7-, 10-, and 14-day intervals. Sperm count and motility showed a significant decrease at 14 days as compared to 7 days but not to 3 days. There were no significant differences between motility, the hypoosmotic swelling test, velocity, linearity, motile density, or morphology (with strict criteria). The ideal abstinence interval is between 7 and 10 days not 2-3 days, and motility does not appear to significantly decrease with a long interval between ejaculates.

Analysis of Variance↗
PubMedDate not supplied

Retrograde ejaculation accompanying hyperprolactinemia.

A patient, 38 years of age with 10 years of infertility, suffered from an ejaculation disorder for 2 years. Based on a diagnosis of retrograde ejaculation, sperm retained in the bladder was collected and homologous artificial insemination was carried out, but pregnancy was not achieved. The subject was examined at the Department of Urology and hormone tests were conducted showing hyperprolactinemia, hypogonadotropinemia, and hypotestosteronemia. A CT scan showed a pituitary tumor. Administration of 7.5 mg/day of bromocriptine was initiated to treat this tumor. Antegrade ejaculation recurred 1 month after administration, and pregnancy was achieved from normal sexual intercourse 5 months after administration.

Adult↗
PubMedDate not supplied

Stimulation of ejaculated domestic cat sperm motility with caffeine, pentoxifylline, and 2'-deoxyadenosine.

Sperm motility patterns of cryopreserved domestic cat ejaculates treated at 37 degrees C with 1 mM caffeine, pentoxifylline, or 2'-deoxyadenosine were analyzed using computer-assisted semen analysis (CASA). The percent motility (MOT), curvilinear velocity (VLC), straight-line velocity (VSL), linearity (LIN), and amplitude of lateral head displacement (ALH) were measured for each group following 15 min of treatment. Motility indices were examined during a 6-h treatment period to determine the effect of each chemical on sperm longevity. Caffeine, pentoxifylline, and 2'-deoxyadenosine each increased (p > .05) the MOT and VCL of the ejaculates compared to the controls. The longevity of the treated and control samples were not significantly different throughout the incubation period. These results, similar to previous findings with cryopreserved epididymal cat sperm, demonstrate that motility stimulants can significantly elevate the MOT and VCL of cryopreserved ejaculated cat sperm without having deleterious effects on longevity.

Animals↗
PubMedDate not supplied

Pelvic floor muscles and sphincters during erection and ejaculation.

The pelvic floor muscles (puborectalis [PR], levator ani [LA]) and external anal (EAS) and urethral sphincters (EUS) were studied during erection and ejaculation in 12 mongrel dogs. The animals were anesthetized and the response of PR, LA, EAS, and EUS to electroejaculation (EE) was evaluated. Penile tumescence and rigidity as well as increase of the EMG activity of the aforementioned muscles and sphincters occurred. The rigidity and EMG activity increased as the voltage and current of EE continued to increase until ejaculation occurred at a mean voltage of 11.1 +/- 1.2 V and current of 122.4 +/- 14.4 mA. The increased PR activity might express the prostatic secretions into the posterior urethra. LA contraction seems to elevate the prostate and partially straightens the prostato-membraneous urethral kink that might occur during erection. The EAS and EUS contractions are believed to abort the urge to defecate or urinate and prevent leak of feces, flatus, or urine during coitus. The rhythmic EUS contraction at ejaculation might act as a "suction ejection pump," sucking the genital fluid into the posterior urethra while being relaxed and ejecting it into the bulbous urethra upon contraction.

Animals↗
PubMed1997

Efficacy of a topical agent SS-cream in the treatment of premature ejaculation: preliminary clinical studies.

SS-cream is a topical agent for treating premature ejaculation (PE) which is made with extracts from 9 natural products. We evaluated the efficacy of SS-cream in the treatment of PE. An open pilot study was performed in 186 patients with PE. The mean ejaculatory latency from intromission to ejaculation was 1.5 minutes. Sixty-four of the 186 patients (34.4%) were combined with mild erectile dysfunction in whom penile rigidity was not sufficient to be satisfied in sexual activity. Patients were instructed to apply 0.1 gm. of SS-cream on the glans penis 1 hour before sexual contact and to wash out the cream before sexual intromission. Patients were asked to complete a report form including ejaculatory latency, the degree of satisfaction in the sexual lives of both themselves and their partners, and any adverse effects after each application. One hundred and sixty-six out of 186 patients (89.2%) reported they were satisfied with the application of the SS-cream and the mean ejaculatory latency was significantly prolonged to 10.89 +/- 5.60 minutes. The mean ejaculatory latency was 9.85 +/- 3.58 minutes in 52 out of 64 patients (81.2%) with mild erectile dysfunction. There was no significant difference in the changes of ejaculatory latencies between patients with pure PE and patients with mild erectile dysfunction. Twenty patients (10.8%) claimed to have no changes of ejaculatory latencies after the application of SS-cream. Adverse effects were noted in 11 patients (5.9%), which were mild local irritation symptoms in 7 patients, and delayed ejaculation of more than 30 minutes in 4 patients, the symptoms subsided spontaneously within 4 hours. These results indicate SS-cream is effective in the treatment of PE and also PE combined with mild erectile dysfunction with a few side effects. Further studies on the action mechanisms of SS-cream and a double blind placebo-controlled trial are needed.

Administration, Topical↗
PubMed2000

The role of mounts and intromissions in triggering ejaculation in rats.

Eight male rats copulated with an estrus female with an open vagina (NF) and an estrus female with the vagina covered by adhesive tape (CF). Experimental sessions were composed of two phases. During Phase 1 the males copulated with NF or with CF females until 4 intromissions or 4 mount bouts were displayed respectively. In Phase 2 the males copulated alternately with NF or CF according to three schedules: (1) a sequence two mount bouts with a CF female followed by one intromission, (2) a sequence one intromission followed by two mount bouts with a CF female, and (3) a sequence one intromission followed by four mount bouts with a CF female. All of these sequences were repeated until ejaculation. Ejaculation occurred in 95.8% of cases within one minute after the last intromission during copulation with the CF female. The results of this study indicate that: (1) the number of intromissions displayed during Phase 2 does not depend on the character of the copulatory behaviour displayed during Phase 1, (2) at least two intromissions are displayed before ejaculation, and (3) the tactile stimulation of the glans of penis plays a crucial role in the ejaculatory seminal reflex.

Analysis of Variance↗
PubMed1999

[Retroperitoneal lymphadenectomy and disorders of ejaculation].

Retrograde ejaculation is a frequent and permanent complication after bilateral retroperitoneal lymphadenectomy (RPLND). Seminal emission and ejaculation are primarily under sympathetic control. Several studies after RPLND in patients with nonseminomatous testis cancer proved the role of preservation of the efferent fibers originating from the lumbar sympathetic ganglia. Based on the results of anatomical studies, a modified unilateral operative technique and nerve-sparing approach permit to preserve normal anterograde ejaculation without reduction of long-term survival.

Ejaculation↗
PubMed1999

Comparison of sertraline to fluoxetine with regard to their efficacy and side effects in the treatment of premature ejaculation.

OBJECTIVE: In the present study, two different serotonin re-uptake inhibitors were compared with regard to their efficacy and side effects in the treatment of premature ejaculation. METHODS: Fifty-seven patients with complaint of premature ejaculation were included in the study. Patient ages ranged from 21 to 45 years (mean age 32 +/- 2.6). They had a regular sexual life and were normal after GRISS psychological test and psychiatric evaluation. The patients were randomized into two groups according to the drugs given. Twenty-six patients aged between 21 to 36 years (mean age 27 +/- 1.1) received fluoxetine 20 mg/day for one week and 40 mg/day thereafter (group I). Thirty-one patients aged between 21 to 45 (mean age 34 +/- 1.7) received sertraline 50 mg/day (group II). All the patients and partners were re-evaluated 4 and 8 weeks after the treatment. The results were classified as unsuccessful, improvement and cure. Mann Whitney-U and Pearson chi-square tests were used for statistical analysis. RESULTS: In the fluoxetine group, 8 (30.8%) patients cured, improvement in 11 (42.3%) and failure in 7 (26.9%). In the sertraline group, 12 (38.7%) patients cured, improvement in 10 (32.3%) and failure in 9 (29%). Side effects in group I were nausea in 3, headache in 1 and insomnia in 2 (total 6 patients, 23%). In group II, we observed nausea in 2 and mouth dryness in 6 (total 8 patients, 25.8%). No patients were excluded from the study due to side effects. CONCLUSION: Our results show that different serotonin re-uptake inhibitors have the same efficacy and side effects in the treatment of premature ejaculation.

Adult↗