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PubMed1984

Human sperm characteristics during frequent ejaculation.

Sperm concentration, morphology, DNA condensation and nuclear protein pattern as well as sperm adenylate cyclase were evaluated in semen samples provided by 7 volunteers every 8 h for 2 days. During the observation period, sperm concentration and total sperm number decreased but began to return towards normal after a 3-day abstinence period. No increase in the proportion of immature sperm cells was observed by light microscopy. Total adenylate cyclase (EC 4.6.1.1) increased significantly per cell, due to an increase in the soluble component while the particulate component remained relatively constant. Microflow fluorometry revealed no consistent alterations in the DNA or nuclear protein distribution. We conclude that although a high frequency of ejaculation does not disturb the conventional measures of sperm integrity, such as DNA condensation, there are major changes in at least one biochemical measurement, the activity of soluble adenylate cyclase.

Adenylyl Cyclases↗
PubMed1989

Adrenal-pituitary-gonadal relationships and ejaculate characteristics in captive leopards (Panthera pardus kotiya) isolated on the island of Sri Lanka.

In Study 1, semen was collected using a standardized electroejaculation procedure. Males (N = 8) produced ejaculates with a high incidence of sperm abnormalities (77 +/- 3.3%). After electroejaculation under anaesthesia, serum cortisol concentrations increased (P less than 0.05), while testosterone concentrations decreased (P less than 0.05) and LH and FSH concentrations were unchanged (P less than 0.05) over a 2-h bleeding period. In Study 2, male and female leopards were bled at 5-min intervals for 3 h and given (i.v.): (1) saline (N = 2/sex); (2) GnRH (1 microgram/kg body weight) 30 min after the onset of sampling (N = 5/sex); or (3) ACTH (250 micrograms) at 30 min followed by GnRH 1 h later (N = 5/sex). Basal concentrations of serum LH, FSH and cortisol were comparable (P greater than 0.05) between male and female leopards. After GnRH, peak LH concentrations were 2-fold greater (P less than 0.05) in males than females while FSH responses were similar. In males, testosterone concentrations increased 2-3-fold following GnRH. After ACTH, serum cortisol concentrations doubled within 15 min in both sexes. Administration of ACTH 1 h before GnRH did not affect GnRH-induced LH or FSH release (P greater than 0.05); however, testosterone secretion was only 30% of that observed after GnRH alone (P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocorticotropic Hormone↗
PubMed2001

Characterization of northern pintail (Anas acuta) ejaculate and the effect of sperm preservation on fertility.

Northern pintail duck semen and sperm traits were characterized, and the fertility of cold-stored spermatozoa was investigated using artificial insemination. Excellent quality ejaculates containing high proportions of motile spermatozoa were collected from drakes within 20 s by a massage technique. Semen was collected in Beltsville poultry semen extender, pooled and cold-stored (4 degrees C) for 0, 24, 48 or 72 h. Hens were inseminated with 100 microl twice a week, and eggs were assessed for fertilization and hatch success. Fertilization success was similar (P > 0.05) for semen cold-stored for 0 (51.6%), 24 (51.5%), 48 (41.1%) and 72 h (22.3%; P > 0.05). Similar (P > 0.05) percentages of fertilized eggs hatched to live offspring (73.1, 71.4, 87.0 and 80.0%, respectively). Fresh semen was also equilibrated with 1 or 4% dimethylsulphoxide or glycerol, and cryopreserved at the following rates: (1) approximately 60 degrees C min(-1) (in liquid nitrogen [LN(2)] vapour) for 10 min; (2) 1 degrees C min(-1) to -20 degrees C, LN(2) vapour for 10 min; and (3) 1 degrees C min(-1) to -35 degrees C, all followed by immersion in LN(2). After thawing for 30 s at 37 degrees C or 20 min at 4 degrees C, sperm motility and viability were assessed. The highest numbers of motile spermatozoa were recovered after slow-fast freezing (2) and thawing at 0 degrees C (P < 0.05), but survival was inadequate to allow artificial insemination. Nonetheless, cold storage provides an effective means of short-term storage with no loss of fertility in this waterfowl species.

Animals↗
PubMed2001

Females receive a life-span benefit from male ejaculates in a field cricket.

Mating has been found to be costly for females of some species because of toxic products that males transfer to females in their seminal fluid. Such mating costs seem paradoxical, particularly for species in which females mate more frequently than is necessary to fertilize their eggs. Indeed, some studies suggest that females may benefit from mating more frequently. The effect of male ejaculates on female life span and lifetime fecundity was experimentally tested in the variable field cricket, Gryllus lineaticeps. In field crickets, females will mate repeatedly with a given male and mate with multiple males. Females that were experimentally mated either repeatedly or multiply lived more than 32% longer than singly mated females. In addition, multiply mated females produced 98% more eggs than singly mated females. Because females received only sperm and seminal fluid from males in the experimental matings, these life-span and fecundity benefits may result from beneficial seminal fluid products that males transfer to females during mating. Mating benefits rather than mating costs may be common in many animals, particularly in species where female mate choice has a larger effect on male reproductive success than does the outcome of sperm competition.

Animals↗
PubMedDate not supplied

Search and identification of spermatozoa and spermatids in the ejaculate of non-obstructive azoospermic patients.

OBJECTIVE: To search and to identify spermatozoa and spermatids, present in the ejaculate of non-obstructive azoospermic patients. MATERIALS AND METHODS: 27 patients, aged between 18 and 48 years, with initial diagnosis compatible with non-obstructive azoospermia, underwent up to 3 seminal samples, with assessment of macroscopic and microscopic parameters differentiated for each sample. In the first sample, 5 microL of semen were analyzed in a Horwell chamber in order to assess the presence or absence of spermatozoa. The procedure was repeated with 2 other aliquots. In the absence of spermatozoa, the entire sample was transferred to a conic tube and following centrifugation the sediment was freshly analyzed. The second seminal sample was collected only when no spermatozoa were found in the first sample and the research was performed in the same way. In cases where spermatozoa were not seen, the sample was centrifuged and the obtained sediment was stained by the panoptic method and observed under common light microscopy (1250X). The third seminal sample was collected only in cases when patients had not shown spermatozoa in the first and second seminal samples. RESULTS: 4/27 (14.8%) patients presented spermatozoa in the first seminal sample and 6/23 (26.1%), in the second seminal sample. No spermatozoa were seen in the third sample, however, 11/17 (64.7%) presented spermatids. CONCLUSION: In clinical situations where the initial diagnosis is non-obstructive azoospermia, one single routine seminal analysis is not enough to confirm this diagnosis and the analysis of the centrifuged sediment can have relevant clinical consequences. Among patients considered non-obstructive azoospermic, when duly assessed, 37% presented spermatozoa and 64.7%, spermatids.

Adolescent↗
PubMed2006

Two-step cluster procedure after principal component analysis identifies sperm subpopulations in canine ejaculates and its relation to cryoresistance.

A 2-step clustering procedure, using indexes derived from principal component analysis, was used to disclose sperm subpopulations within the canine ejaculate and its relationship to sperm cryoresistance. Semen from 4 dogs was frozen-thawed by a standard protocol: before freezing, computer-assisted sperm analysis of motility and morphometry were performed; after thawing, motility analysis was performed again; and cryoresistance was estimated as the percent changes in progressive motility and sperm velocities after thawing. We used indexes derived from principal component analysis (sperm velocity index [SVI] and sperm motility index [SMI]) and the SPSS 2-step cluster method to disclose sperm subpopulations. The 2-step clustering procedure revealed the existence of 6 subpopulations. Subpopulations 4 and 6 were characterized by high values of both SVI (>200 arbitrary units) and SMI (>90 arbitrary units), subpopulations 2 and 3 were characterized by medium values (SVI 100 to 130; and SMI 30 to 40), and subpopulations 1 and 5 were characterized by low values (SVI < 100; SMI < 30). The distribution of sperm subpopulations was completely different among dogs. Four sperm subpopulations based in morphometric parameters of the sperm head and midpiece were revealed. Models including SVI and SMI indexes explained curvilinear velocity (R(2) = 0.997; P < .001), straight-line velocity (R(2) = 0.98; P < .001), and average velocity (R(2) = 0.99; P < .0001) postthaw.

Animals↗
PubMed2005

Psychobiological correlates of delayed ejaculation in male patients with sexual dysfunctions.

The pathogenesis of delayed ejaculation (DE) is rather unknown, though the contribution of various psychological, marital, hormonal, and neurological factors has been advocated. In this study we systematically investigated the relative relevance of the aforementioned factors in 1,632 men who were seeking medical help for sexual dysfunction. The severity of DE was classified according to Kaplan criteria. Mild and moderate forms of DE (MMDE) recognized different risk factors than the most severe ones (anejaculation or severe DE [ASDE]). ASDE was essentially coupled with the presence of neurological diseases or with the use of serotoninergic drugs. Serotoninergic drugs also significantly increase (by at least 10-fold) the risk for MMDE, which, however, was also coupled with other relational factors (eg, partner's impaired climax, patient's hypoactive sexual desire [HSD]) or intrapsychic factors (eg, stress at work). At multiple regression analysis, some organic pathological conditions (such as psychiatric disorders and hypogonadism) were also associated with MMDE. In particular, hypogonadism retained significance for DE even after adjustment for HSD (adjusted odds ratio = 2.08 [1.11-3.89]; P < .05), suggesting other effects of testosterone deficiency on the ejaculatory reflex besides reduced libido. In conclusion, the present study demonstrates that multiple psychobiological determinants are associated with DE, a still obscure condition that substantially impairs psychosexual equilibrium of the couple.

Ejaculation↗
PubMed1997

Unprotected anal intercourse in gay men: the resolution to withdraw before ejaculating.

734 gay men who had recently engaged in unprotected anal intercourse reported self-justifications they used at the time. A common self-justification involved a resolution to withdraw before ejaculating. Compared with other self-justifications, this resolution was associated with a "last minute" rather than a "premeditated" decision to have unprotected anal intercourse, suggesting that the resolution derived just from "heat of the moment" thinking. Implications for AIDS education are discussed.

Adult↗
PubMed2006

Genetic parameters for various random regression models to describe total sperm cells per ejaculate over the reproductive lifetime of boars.

The objective of this study was to model the variances and covariances of total sperm cells per ejaculate (TSC) over the reproductive lifetime of AI boars. Data from boars (n = 834) selected for AI were provided by Smithfield Premium Genetics. The total numbers of records and animals were 19,629 and 1,736, respectively. Parameters were estimated for TSC by age of boar classification with a random regression model using the Simplex method and DxMRR procedures. The model included breed, collector, and year-season as fixed effects. Random effects were additive genetic, permanent environmental effect of boar, and residual. Observations were removed when the number of data at a given age of boar classification was < 10 records. Preliminary evaluations showed the best fit with fifth-order polynomials, indicating that the best model would have fifth-order fixed regression and fifth-order random regressions for animal and permanent environmental effects. Random regression models were fitted to evaluate all combinations of first- through seventh-order polynomial covariance functions. Goodness of fit for the models was tested using Akaike's Information Criterion and the Schwarz Criterion. The maximum log likelihood value was observed for sixth-, fifth-, and seventh-order polynomials for fixed, additive genetic, and permanent environmental effects, respectively. However, the best fit as determined by Akaike's Information Criterion and the Schwarz Criterion was by fitting sixth-, fourth-, and seventh-order polynomials; and fourth-, second-, and seventh-order polynomials for fixed, additive genetic, and permanent environmental effects, respectively. Heritability estimates for TSC ranged from 0.27 to 0.48 across age of boar classifications. In addition, heritability for TSC tended to increase with age of boar classification.

Age Factors↗
PubMed1989

Effects of sexual stimulation, with and without ejaculation, on serum concentrations of LH, FSH, testosterone, cortisol and prolactin in stallions.

Six lighthorse stallions with previous sexual experience were used to determine the short-term effects of sexual stimulation (SS; 5 min exposure to an estrous mare), SS plus ejaculation (SSE), and no stimulation (control) on serum concentrations of LH, FSH, testosterone, cortisol and prolactin. Stallions received one treatment per day on d 1, 4 and 7. Treatments were assigned such that each stallion 1) received each treatment once and 2) experienced a unique sequence of treatments. Neither SS nor SSE had any consistent effects on LH or FSH concentrations. Testosterone concentrations during control bleedings increased (P less than .05) with time. This increase was suppressed (P less than .05) by both SS and SSE. Cortisol concentrations increased (P less than .05) immediately after SS and SSE. Cortisol concentrations also tended to increase during the control bleedings, but only in stallions that previously had been exposed to SS or SSE. Prolactin concentrations increased (P less than .05) immediately after SS and SSE and tended to rise during control bleedings in stallions previously exposed to SS or SSE. We conclude that 1) prolactin and cortisol were secreted rapidly in response to SS and SSE, 2) the rise in cortisol concentrations likely suppressed testosterone secretion within the next hour, and 3) stallions appeared to associate the distant sounds of other stallions with their own previous exposure to SS and SSE, resulting in a cortisol response (and perhaps a prolactin response) even in the absence of direct stimulation.

Animals↗
PubMed1982

Surface components of ejaculated chimpanzee sperm.

Surface components of ejaculated chimpanzee sperm were radiolabeled by enzymatic iodination with lactoperoxidase and Na125I. The sperm were lysed and the labeled components analyzed on SDS-7.5% polyacrylamide gels. Electrophoresis of solubilized radioactivity resolved four components with approximate molecular weights of 72,000, 49,000, 25,000 and 17,000 daltons. To identify components, which might be adsorbed to the chimpanzee sperm surface from seminal secretions, seminal plasma was labeled. Electrophoresis of labeled seminal plasma resolved three components with approximate molecular weights of 63,000, 26,000, and 17,000 daltons, two of which comigrated with a labeled sperm surface component.

Animals↗
PubMed1987

Prostatic ejaculate in assigned males with 46,XX congenital adrenal hyperplasia.

Two assigned males with 46,XX congenital virilizing adrenal hyperplasia due to 11 beta-hydroxylase deficiency reported an ejaculation of thick fluid. Chemical analysis revealed that the fluids bore a resemblance to normal prostatic fluids. Extreme virilization in utero seems to have produced both complete virilization of external genitalia and development of a prostate.

Adrenal Hyperplasia, Congenital↗
PubMedDate not supplied

Free radical-induced liquefaction of ejaculated human semen: a new dimension in semen biochemistry.

Even though the aminopeptidase and amylase are the major liquefying factors in the liquefaction process of the ejaculated semen-coagulum, the exact nature of "switching on" phenomena has not been elucidated yet. Monitoring the rate of production of the asborbyl radical, an indirect method for oxyradical-stress measurement, this prima facie study reports the involvement of oxygen radical in the liquefaction process of coagulated semen.

Dehydroascorbic Acid↗
PubMed2000

Penile vibratory threshold changes with various doses of SS-cream in patients with primary premature ejaculation.

SS-cream made with extracts from natural products is a topical agent for treating premature ejaculation (PE). In order to elucidate the penile vibratory threshold changes and clinical effects of various doses of SS-cream, 53 patients with primary PE were investigated in a double-blind randomized placebo-controlled study. The mean age was 37.3 +/- 6.4 years and mean ejaculatory latency was 1.37 +/- 0.52 minutes. Neither the patients nor their sexual partners were satisfied with their sexual lives. Vibratory threshold at the glans penis, penile shaft, scrotum and index finger were measured using a biothesiometer twice during the screening period and three times one hour after the application of respective creams (SS-cream 0.05, 0.10. 0.15, 0.20 gm and placebo 0.10 gm) on the glans penis according to the order of the allocation table in a randomized fashion. The efficacy of SS-cream was defined as when the vibration threshold increased by more than 4 microns compared to the value tested during the screening period. The vibratory thresholds at the glans penis increased significantly in a dose-dependent manner after the application of various doses (0.05, 0.10, 0.15, 0.20 gm) of SS-cream (p < 0.001), and the efficacy of SS-cream on the penile vibration threshold increased according to the increased dosage (penile shaft: 48.4, 51.6, 54.8, 64.5%, glans penis: 58.1, 67.7, 77.4, 83.9%, respectively). With these results, we concluded that SS-cream increased the penile sensory threshold dose dependently, and therefore it is clinically effective for treating the heightened penile sensory response in patients with PE.

Adult↗
PubMed2005

Circulating neuroactive C21- and C19-steroids in young men before and after ejaculation.

Twelve neuroactive and neuroprotective steroids, androgens and androgen precursors i.e. 3alpha,17beta-dihydroxy-5alpha-androstane, 3alpha-hydroxy-5alpha-androstan-17-one, 3alpha-hydroxy-5beta-androstan-17-one, androst-5-ene-3beta,17beta-diol, 3beta,17alpha-dihydroxy-pregn-5-en-20-one (17alpha-hydroxy-pregnenolone), 3beta-hydroxy-androst-5-en-17-one (dehydroepiandrosterone, DHEA), testosterone, androst-4-ene-3,17-dione (androstenedione), 3alpha-hydroxy-5alpha-pregnan-20-one (allopregnanolone), 3beta-hydroxy-pregn-5-en-20-one (pregnenolone), 7alpha-hydroxy-DHEA, and 7beta-hydroxy-DHEA were measured using the GC-MS system in young men before and after ejaculation provoked by masturbation. The circulating level of 17alpha-hydroxypregnenolone increased significantly, whereas the other circulating steroids were not changed at all. This fact speaks against the hypothesis that a drop in the level of neuroactive steroids, e.g. allopregnanolone may trigger the orgasm-related increase of oxytocin, reported by other authors.

17-alpha-Hydroxypregnenolone↗
PubMed1986

Parthenogenesis in medium white turkeys selected for low and high semen ejaculate volumes.

The incidence of parthenogenesis in two lines of Medium White turkeys subjected to bidirectional selection for semen ejaculate volume was examined during the ninth and tenth generations. A significant increase in the incidence of parthenogenesis was observed in both generations of the line selected for low semen volume. The study suggests that selection for low semen volume may result in the stimulation of parthenogenesis as a means of genome survival.

Animals↗
PubMed1991

Genetic variation in the incidence of pipped eggs in turkeys selected for low and high semen ejaculate volume.

Genetic variation in embryonic mortality, expressed as embryos that pip their eggshell but do not hatch, was investigated in turkeys selected for low and high semen ejaculate volume (SEV). Through five generations (Generations 10 to 14, inclusive) mean heritability estimates for pipped eggs were .21 and .08 in the low- and high-SEV lines, respectively. Estimates of sire, dam, and within-hatch components of variance suggest greater environmental and maternal effects than genetic influences on the incidence of pipped eggs in turkeys.

Animals↗
PubMed2006

Role of transrectal ultrasonography in the evaluation of azoospermic men with low-volume ejaculate.

OBJECTIVE: The purpose of this prospective study was to evaluate the incidence of distal ejaculatory system defects with transrectal ultrasonography (TRUS) among patients evaluated for azoospermia. METHODS: Forty-two patients with low-volume ejaculate and azoospermia were evaluated by physical examination, serum follicle-stimulating hormone and luteinizing hormone level determination, karyotyping, selective screening for cystic fibrosis mutations, and TRUS. RESULTS: On physical examination, in 29 patients (69%), either 1 (12 patients) or both (17 patients) of the vasa deferentia could not be palpated. In the group of 17 patients with bilateral involvement of the vasa deferentia, the ultrasonographic imaging universally showed bilateral absence or hypoplasia of the seminal vesicles with bilateral agenesis of the vasa deferentia and nonvisualization of both ejaculatory ducts. In the patients with a unilateral abnormality on physical examination, the ultrasonographic imaging showed absence of the ipsilateral seminal vesicle in 7 patients and the hypoplastic seminal vesicle in 5. In the group of 13 patients with normal physical examination findings, a variety of obstructive causes were diagnosed by TRUS examination. CONCLUSIONS: According to this study, TRUS appears to be a sensitive method for evaluating the anatomy of the distal ejaculatory system. Its safety and low costs make it a good alternative to the other invasive and expensive methods.

Adult↗