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PubMed1983

Penile reflexes in intact rats following anesthetization of the penis and ejaculation.

Application of the topical anesthetic pontocaine (tetracaine hydrochloride) to the penis and preputial sheath virtually abolished the display of penile reflexes by intact rats. When pontocaine was applied immediately following ejaculation in copula, however, normal genital reflexes were observed in the majority of rats, albeit with a prolonged latency to the first erection relative to the control test. These same animals were, nonetheless, unable to achieve intromission when returned to the mating arena despite repeated mounting attempts. These data suggest that sensory input to the genitalia is generally necessary for the display of penile reflexes in the rat. However, stimuli associated with copulation can override the suppressive effect of sensory loss of these reflexes, presumably due to removal of supraspinal inhibition.

Animals↗
PubMed1984

Boar sperm cytoplasmic droplets: their ultrastructure, their numbers in the epididymis and at ejaculation and their removal during isolation of sperm plasma membranes.

Cytoplasmic droplets of the boar are progressively lost from the flagellum of boar spermatozoa during epididymal transit, at ejaculation and during the nitrogen cavitation technique for isolation of plasma membranes. Apparently very fragile, these structures are broken up in the fluids of the reproductive tract and in the buffer used during the nitrogen cavitation procedure. The maximal potential contamination of cytoplasmic droplet internal vesicular membranes in plasma membrane fractions was determined to be 2.2% of the entire membrane surface area collected. The highly sensitive silver-stained, two-dimensional (2-D) polyacrylamide (PAGE) gels of boar sperm plasma membranes did not reveal cytoplasmic droplet, internal membrane, marker polypeptides, further demonstrating the high purity of plasma membrane preparations. In addition, freeze-fracture demonstrates that the internal membranes of the cytoplasmic droplet show few intramembranous particles and these may contribute little protein to plasma membrane preparations. The presence of two forms of vesicular elements in boar sperm cytoplasmic droplets (typical vesicles and collapsed vesicles) is described.

Animals↗
PubMed1977

Dynamic activity of bladder neck and external sphincter in ejaculation.

The bladder neck shows a typical electromyographic pattern in ejaculation. It consists of periods of heightened activity rhythmically alternating with intervals of reduced activity signifying muscular contraction and relaxation. This behavior of the bladder neck is confined to its ventral part. Concurrently, the external sphincter shows a short period of increased activity before the typical rhythmical pattern which corresponds to that of the ventral bladder neck.

Animals↗
PubMed1977

Postcoital-voiding insemination: technique for patients with retrograde ejaculation and infertility.

Three patients with infertility secondary to retrograde ejaculation demonstrated motile sperm in their urine after coitus. These patients were instructed to alkalinize their urine and void directly into the vagina after intercourse. The technique was called "postcoital-voiding insemination." Three pregnancies have resulted. The technique appears to be a good alternative to bladder catheterization and artificial insemination.

Adult↗
PubMed1978

Premature ejaculation: new electrophysiologic approach.

A new diagnostic investigation for premature ejaculation is described. Although the neurophysiologic basis of the test is unknown, it could be a good method for differentiating organic from psychologic ejaculatory dysfunction.

Adolescent↗
PubMed1980

Values for zinc in whole semen, fractions of split ejaculate, and expressed prostatic fluid.

Since the prostate gland secretes specific substances, several investigators have suggested that measurement of these products may be useful for the evaluation of prostatitis. In our laboratory we have measured seminal zinc as a marker of prostatic secretion to establish normal values and define the confidence limits for this assay. Zinc assays were performed on whole semen, fractions of the split ejaculate, and expressed prostatic fluid from among a population of 456 men. We hope that these data will be useful when compared with data from patients with prostatic disease.

Ejaculation↗
PubMed1987

Massive post-ejaculation hematuria.

The case of a twenty-nine-year-old white male with massive post-ejaculation hematuria, an entity distinct from hemospermia, is described. The site of bleeding was found to be large varicosities located at the apex of the prostate. Fulguration of the veins produced complete resolution of the bleeding.

Adult↗
PubMed1993

Effect of digital rectal examination (and ejaculation) on serum prostate-specific antigen after twenty-four hours. A randomized, prospective study.

The purpose of this randomized, controlled, clinical trial was to determine the effect of the digital rectal examination (DRE) on the prostate-specific antigen (PSA) serum levels in view of conflicting literature reports and screening methods and misconceptions by physicians. We showed that the DRE had no clinically important effect on PSA values twenty-four hours later. The mean PSA rose from 1.57 to 1.62 ng/mL, similar to the controls. Ejaculation had no meaningful effect on the serum PSA values.

Adult↗
PubMed1991

MDMA produces a conditioned place preference and elicits ejaculation in male rats: a modulatory role for the endogenous opioids.

Methylenedioxymethamphetamine (MDMA) can produce a conditioned place preference (CPP) among rats. The ability of MDMA to produce a CPP was assessed while some rats were under the influence of naltrexone, 56 mg/kg, given 4 h before conditioning. Naltrexone attenuated MDMA's ability to produce a CPP without completely blocking MDMA's effects. Having noticed previously the production of seminal plugs by rats receiving MDMA, the presence of seminal plugs was recorded across the 8 days of conditioning. Roughly half of the rats receiving 6.3 mg/kg of MDMA left plugs during the conditioning period, while over two-thirds of those receiving a combination of MDMA and naltrexone left plugs. A second study, assessing further doses of MDMA, tabulated the drug's effects on the production of seminal plugs across 3 h. Besides eliciting ejaculation, MDMA also led to increased urination and defecation and a loss of body weight. These results support suggestions that the endogenous opioids modulate the reinforcing properties of stimulant drugs and affect male sexuality.

3,4-Methylenedioxyamphetamine↗
PubMed1991

Apomorphine induces ejaculation in chronic decerebrate rats.

Chronically maintained supracollicular decerebrate (CD) rats, but not rats with midthoracic (T10) spinal transections (SPI) or neurologically intact controls, displayed erection and ejaculation following systemic administration of the dopamine (DA) agonist, apomorphine (APO). The response was blocked by pretreatment with the DA receptor antagonist, cis-flupentixol. CD rats, like intact controls, failed to display erections or penile cupping in response to the same mechanical stimulation that elicited short-latency responses in SPI rats. The present results demonstrate excitatory and inhibitory mechanisms of relevance to the copulatory behavior of the male rat that are endemic to the caudal brainstem neurally isolated from forebrain influence.

Animals↗
PubMed2006

Fas ligand in bull ejaculated spermatozoa:A quantitative immunocytochemical study.

Apoptosis, or programmed cell death, provides a way to remove redundant cells at the end of their lifespan and thus acts as a homeostatic mechanism, maintaining the correct number of cells in the body by balancing their production and death. In the testis, this process seemed to play a pivotal role in spermatogenesis. It is generally accepted that Sertoli cells control the germ cell population through one of the best-known apoptotic pathways, the Fas/Fas L paracrine signal transduction system, in which a Fas ligand (Fas L) expressed by Sertoli cells induces apoptosis when it binds with its receptor, Fas, expressed by the germ cells. Recently, we demonstrated the presence of Fas antigen in normal ejaculated spermatozoa from fertile bulls and suggested that this molecule might have a non-apoptotic, defensive role against injuries, especially oxidative stress. We have now investigated whether bull mature, fertile spermatozoa express not only the Fas receptor but also its natural ligand Fas L. Our results indicate that the whole sperm population expresses Fas L. We suggest that Fas L in bull spermatozoa, like in murine spermatozoa, might be able to kill activated lymphocytes and protect the male gamete from damage by the self-immune system or the cytotoxic activity of leukocytes in the female genital tract.

Animals↗
PubMed2005

Erectile dysfunction and premature ejaculation are the most frequently self-reported sexual concerns: profiles of 9,536 men calling a helpline.

OBJECTIVES: To describe the range of sexual problems, as reported by men calling a help-line and to investigate factors associated with help seeking behaviour. METHODS: The study included all calls between 1999 and 2004. The information used for analysis comprised caller's demographic characteristics, the sexual problem reported, previous doctor contacts, coexisting physical and mental health problems. RESULTS: Erectile dysfunction (ED) and premature ejaculation (PE) were the most frequently reported problems (57 and 19.2% respectively). ED-reporting callers were older (OR 0.63 for the ages of 50-59 yrs), with co-morbidities (OR 1.75) and in stable relationship (OR 0.46), while PE-reporting callers were younger (OR 5.83 for the ages of 20-29 yrs), relatively healthy and more likely single (OR 2.62 and OR 2.92 respectively). Type and duration of sexual concern, age, coexisting health problems and marital status relate significantly (p<0.01) with willingness to seek medical help. CONCLUSIONS: The study demonstrates that ED and PE are men's major sexual concerns with personal and interpersonal factors influencing their help-seeking behaviour. Help-lines can serve as a link between health services and callers, while provide useful information for policy formation and improvement of support services.

Adult↗
PubMed2006

Fertilization and pregnancy outcome after intracytoplasmic injection with fresh or cryopreserved ejaculated spermatozoa.

OBJECTIVE: To assess fertilization, implantation, and pregnancy rates in patients undergoing ICSI using fresh and cryopreserved sperm from ejaculated semen samples. DESIGN: Retrospective study. SETTING: Academic and private medical centers. PATIENT(S): One hundred fifty-eight patients. INTERVENTION(S): Intracytoplasmic sperm injection. MAIN OUTCOME MEASURE(S): Fertilization, implantation, and pregnancy rates were evaluated; 61 cycles of ICSI were performed with cryopreserved and 79 cycles of ICSI were performed with fresh spermatozoa. Also, we divided the outcomes according to the semen characteristics, normozoospermia, oligozoospermia, asthenozoospermia, and oligoasthenozoospermia. RESULT(S): Overall, normal-fertilization rates were higher using fresh sperm (73.8%) compared with cryopreserved sperm (68.7%). Cycles performed in patients with normozoospermia or oligozoospermia had similar fertilization, implantation, and pregnancy rates using fresh or cryopreserved sperm. When asthenozoospermic and oligoasthenozoospermic semen samples were used, the normal-fertilization rate was higher with fresh sperm compared with cryopreserved sperm. However, implantation and pregnancy rates were similar in fresh and cryopreserved sperm samples from patients with asthenozoospermia or oligoasthenozoospermia. CONCLUSION(S): Semen with abnormalities in the motility may be more susceptible to sperm cryopreservation damage, resulting in lower fertilization rates. However, once the oocyte is fertilized, implantation and pregnancy rates are similar to those in patients with oligozoospermia and normozoospermia.

Adult↗
PubMed2005

Intra-specific variation in strategic ejaculation according to level of polyandry in Callosobruchus chinensis.

Optimal sperm allocation should differ according to the level of polyandry within a population, because the risk of sperm competition depends on the re-mating frequency of females. We compared the number of sperm ejaculated by males into the female reproductive organ between strains with different levels of polyandry in the adzuki bean beetle, Callosobruchus chinensis (Coleoptera: Bruchidae) when males were reared in different larval densities in a bean. The results showed that males derived from a population with a higher level of polyandry increased ejaculatory expenditure when they were reared under higher larval densities. We discuss the evolutionary correlation of ejaculatory expenditure to the level of polyandry.

Animals↗
PubMed2006

Efficacy of sildenafil citrate in treatment of erectile dysfunction: impact of associated premature ejaculation and low desire.

OBJECTIVES: To assess the effect of premature ejaculation (PE) and low desire on the efficacy and satisfaction rate of sildenafil in the treatment of erectile dysfunction (ED). METHODS: A total of 586 male patients with ED in association with and without PE or low desire were enrolled in this study. Patients were screened for ED using the International Index for Erectile Function. All patients were also screened for PE and low desire. We compared the responses to the erectile function domain, questions 3 and 4, before and after sildenafil in patients with and without PE or low desire. Overall satisfaction and global efficacy question responses were also assessed in all patients. RESULTS: The mean age +/- SD was 58 +/- 6.4 years. Significant associations were found between the increased duration and severity of ED and the decreased rate of overall satisfaction. Before sildenafil administration, significant differences were found in the erectile function domain, Q3 and Q4 between patients with and without PE or low desire. After sildenafil administration, no significant differences were found in those assessment variables and the presence or absence of PE and low desire. No significant differences were found between the global efficacy question response and the overall satisfaction rate between patients with and without PE or low desire. CONCLUSIONS: The efficacy of sildenafil was negatively affected by an increased duration and severity of ED; however, global efficacy and overall patient satisfaction were not attenuated by PE or low desire.

Ejaculation↗
PubMedDate not supplied

Effect of chemotherapy on elevated ejaculation time and deteriorated semen characteristics consequent to bovine trypanosomiasis.

The effect of the trypanocidal drug Novidium on elevated ejaculation time and deteriorated semen characteristics was studied in Zebu cattle infected with T. vivax and T. congolense. Two groups, comprising six bulls per group, were infected with Trypanosoma vivax or Trypanosoma congolense while three bulls served as controls. Chemotherapy was carried out 12 weeks post-infection on three bulls from each group, leaving three bulls untreated while three bulls served as uninfected controls. Blood samples from treated bulls were all negative for trypanosomes 3 days post-chemotherapy. The animals also had normal body temperature. As the study progressed, clinical signs associated with trypanosomiasis, such as anaemia and cachexia, disappeared gradually in treated bulls. There was some improvement in semen characteristics of some of the bulls at 10 weeks post-chemotherapy with Novidium. However, all bulls infected with T. vivax or T. congolense irrespective of Novidium chemotherapy still had poor semen characteristics manifested by all or some of the following: decreased volume of semen, oligospermia, azoospermia and elevated incidence of spermatozoa morphological abnormalities. They were thus unsuitable for breeding.

Animals↗