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At least 19 recordsLinked to original sources
PubMed1983

Effects of non-medicated and copper IUDs on sperm migration.

35 women of proven fertility who were scheduled for surgical sterilization by salpingectomy were selected for this study; 15 control patients, 10 patients using the Multiload (ML) Cu 250 IUD, and 10 fitted with nonmedicated IUDs. Increased copper concentration did not affect sperm receptivity by the cervical mucus, but did significantly affect sperm motility and survival. Nonmedicated IUDs did not interfere with sperm transport in the oviduct. ML Cu IUDs inhibited sperm transport in the oviduct. The effects of the ML Cu IUD on sperm migration were more evident at the tubal level than at the cervical level.

Biology↗
PubMed1987

Inhibition of sperm transport and fertilization in superovulating ewes.

In Experiment 1, all ewes were treated with follicle stimulating hormone (FSH-P) to induce superovulation. Ewes came into natural estrus or were treated with prostaglandin F(2)alpha (PGF(2)alpha) or 6-methyl-17-acetoxyprogesterone (MAP) to regulate the time of estrus. The ewes were mated during estrus and necropsied 3 h after mating. Regulation of estrus with either compound reduced the number of sperm recovered from the cervix, uterus, and oviducts and increased the proportions of sperm recovered from the cervix and uterine body that were immotile, dead, or had disrupted membranes. In Experiment 2, all ewes were in natural estrus. They either ovulated naturally or were superovulated, and ewes in each group were necropsied at 3 or 23 h after mating. Superovulation reduced the number of sperm in oviducts, uterus, and anterior segments of the cervix at both time intervals and increased the proportions of sperm that were immotile, dead, or had disrupted membranes. In Experiment 3, of 3x2 design, ewes were in either natural estrus or estrus regulated with PGF(2)alpha or with MAP; they ovulated naturally or were superovulated. Ewes were necropsied 3 d after mating and ova were examined. Both regulation of estrus and superovulation reduced the proportion of ova that were fertilized and reduced the number of accessory sperm attached to fertilized ova.

Journal Article↗
PubMed1996

Sperm transport and survival post-application of a new spermicide contraceptive. Advantage 24 Study Group.

The present study was undertaken to evaluate the effectiveness of Advantage 24 to inhibit sperm transport and survival when applied at 24 hours, 12 hours, and 15-30 minutes prior to a single act of intercourse. Conceptrol, applied at 15-30 minutes before intercourse, was employed as the comparative spermicide. One-hundred-thirty-nine women, aged 22 to 45 years, were enrolled into the study and 111 completed the trial. The ability of the spermicides to immobilize sperm was assessed by postcoital testing (PCT) and by examining the proportion of sperm immobilization failure (SIF) rates. SIF was a postcoital test result with > or = 10 sperm with progressive motility (either sluggish or rapid) per x 400 power field. Conceptrol and Advantage 24 used at 15-30 minutes were similar with respect to their ability to inactivate sperm (0% and 2% SIF, respectively, p = 0.5). At longer intervals between spermicidal application and intercourse, less inhibition of sperm motility was noted (9% and 14% SIF for 12 and 24 hours, respectively). The present study indicates that Advantage 24 is an effective agent to immobilize sperm. The action of Advantage 24 may decrease if it is applied earlier than 15-30 minutes before intercourse.

Administration, Intravaginal↗
PubMed1982

Demonstration of an early abortifacient effect of norethisterone (NET) in the primate (baboon).

A long-acting injectable contraceptive which provides continuous controlled release of norethisterone (NET) for three months following a single intramuscular injection was tested for antifertility effects in baboons using a low dose of microcapsules (total NET dose 2.5 mg; daily dose approximately 0.03 mg/day) which has no effect on ovarian function or ovulation. The continuous administration of NET during the cycle of conception had no effect on ovulation, fertilization or implantation as evidenced by the occurrence of nine pregnancies following 23 test matings. Pregnancy was diagnosed by the measurement of baboon chorionic gonadotropin hormone and the maintenance of elevated serum progesterone levels past the normal time of menstruation. Six of the nine pregnancies, however, ended in abortion between days 27 and 35 of pregnancy. The remaining three pregnancies continued to term and normal, healthy babies were delivered. Five control baboons included in this study became pregnant and all delivered normal, healthy infants. The results of this study demonstrate that early abortion should be considered as a mechanism of antifertility action of NET when administered continuously in low doses. These findings are contrary to the generally accepted explanation that low-dose synthetic progestins exert their contraceptive effect by inhibiting sperm transport and/or preventing implantation.

Abortion, Spontaneous↗
PubMedDate not supplied

Sperm immobilizing activity of a synthetic bioactive peptide 20-44 of 37-kDa cationic antimicrobial protein (CAP37) of human neutrophils.

We have previously reported that human sperm coincubated with human peripheral blood neutrophils in the presence of complement (C)-fixing antisperm antibody (ASA)-positive sera are rapidly internalized and degraded within the neutrophil phagolysosome. However, the mechanism by which motile sperm are processed within the phagolysosome is unknown. Various spermicidal/antimicrobial proteins contained in azurophilic granules that can be secreted into the phagolysosome may play a role in sperm disposal. In this study, we examined the expression of a 37-kDa cationic antimicrobial protein (CAP37) during sperm phagocytosis and the effect of its synthetic bioactive fragment, Peptide 20-44 (P20-44), on sperm motility, acrosomal integrity, and mitochondrial functionality. CAP37 expression by neutrophils undergoing ASA- and C-dependent sperm phagocytosis was increased as measured by flow cytometry. Exposure of motile sperm to a cationic P20-44, the bioactive antimicrobial fragment of CAP37, resulted in the loss of sperm motility without disruption of the acrosomal membrane. The sperm immobilizing activity (SIA) of P20-44 was modulated by the length of incubation, the concentration of the peptide, and the pH of the assay medium. SIA induced by P20-44 was partially reversible and was unaffected by the presence of anionic heparin or seminal plasma. Similar to the antimicrobial activity of P20-44, the SIA was also dependent on the presence of a disulfide bond between cysteine residues at positions 26 and 42 and was inhibited by Lipid A. However, the mechanism of action of P20-44 on sperm is not totally dependent on the molecule's cationicity, because five other cationic antimicrobial peptides had no detectable effect on sperm viability. Thus, the mechanism of action of P20-44 on human sperm is different from its cationic antibactericidal effect. These findings established that motile human sperm are sensitive to CAP37 or its synthetic bioactive peptide and suggested that this protein could play a role in neutrophil-mediated immune destruction of sperm in the female genital tract. P20-44 of CAP37 may be useful in investigating the regulation of human sperm motility and to construct "hybrid peptides" with enhanced potency as a component of vaginal contraceptive that could doubly be effective by killing infectious agents and inhibiting sperm transport.

Antimicrobial Cationic Peptides↗
PubMed1983

Sperm survival and transport in the female reproductive tract.

Fertilization failure, mostly due to absence of sperm in the oviducts, is a major cause of reproductive inefficiency of farm animals. Sperm may be transported to the oviducts of cattle and sheep within a few minutes after mating or insemination, but these sperm probably fertilize few ova. Slower transport, with establishment of sperm populations in each segment of the reproductive tract, requires a few to several hours. In swine, sperm capable of fertilizing ova reach the oviducts in less than 1 h. Smooth muscle contractions of the reproductive tract, ciliary beats, fluid currents, and flagellar activity of sperm are primary mechanisms of sperm transport. Sperm become hyperactive in the oviducts in association with capacitation. Most sperm in an inseminate drain from the female reproductive tract within a few minutes or hours after insemination; remaining sperm are removed from the tract by slower drainage or phagocytosis. Sperm survival and transport in estrous ewes is reduced drastically by pastures with high estrogen content and by regulating estrus with progestogen or prostaglandin F2 alpha. The cervix is the initial site of inhibition of sperm transport in ewes, and endocrine imbalances probably are the basis of inhibition. Sperm transport problems generally are associated with immobilization and death of sperm in the uterus and anterior segments of the cervix within 2 h after mating. After gilts are inseminated with frozen-thawed semen, relatively few sperm are retained in the reproductive tract, apparently accounting for lowered fertilization rates. Sperm transport has been improved by adding to semen or administering to females such compounds as prostaglandin F2 alpha, oxytocin, estradiol, phenylephrine, or ergonovine. Estradiol, prostaglandin F2 alpha, phenylephrine, and ergonovine administered to rabbits at insemination each increased fertilization rates.

Animals↗
PubMedDate not supplied

Effect of prazosin on sperm transport in male rats.

Our objective was to investigate ejaculation and transport of sperm in the reproductive tract of male rats treated with an alpha-adrenergic receptor antagonist. Males were dosed (s.c.) with vehicle or 1.4 mg/kg prazosin. Sperm recovered in utero and ex vivo from the vas deferens and cauda epididymis were evaluated. Mating behavior and sperm motility were unaffected by prazosin. Prazosin treated males ejaculated fewer sperm (12.58 +/- 8.12 vs. 110.5 +/- 29.15 million), and the distal vas deferens contained fewer sperm (2.72 +/- 0.84 vs. 24.42 +/- 3.25 million) relative to controls. Prazosin-treated males had more sperm in the cauda epididymis relative to controls indicating inhibition of sperm transport to the vas deferens. These data demonstrate that inhibition of sperm transport from the cauda epididymis to the distal vas deferens is related to low ejaculate sperm counts in prazosin treated rats.

Adrenergic alpha-Antagonists↗
PubMed1987

A biochemical basis for 1,2-dibromo-3-chloropropane-induced male infertility: inhibition of sperm mitochondrial electron transport activity.

A rapid decrease in male fertility in laboratory animals exposed to 1,2-dibromo-3-chloropropane (DBCP) has been suggested to be due, in part, to a postglycolytic inhibition of sperm carbohydrate metabolism. The present studies were performed to identify the specific site of DBCP-induced inhibition of intermediary metabolism. 14CO2 generation by epididymal sperm, isolated from Fischer 344 rats, was measured using radiolabeled tricarboxylic acid (TCA) cycle intermediates: acetyl CoA, citrate, alpha-ketoglutarate, and succinate. There was 0-28% inhibition of CO2 generation after addition of 0.5 mM DBCP and 81-98% inhibition with 3 mM DBCP, with all four substrates. The activities of alpha-ketoglutarate dehydrogenase, pyruvate dehydrogenase, malate dehydrogenase, and lactate dehydrogenase were not inhibited by DBCP. Since the DBCP-induced inhibition of metabolism of different substrates to CO2 was similar, and since DBCP did not inhibit enzyme activities of glycolysis or the TCA cycle, a common site of inhibition was suspected. In evaluations of mitochondrial electron transport chain activity, DBCP (3 mM) inhibited oxygen consumption resulting from metabolism of endogenous substrates plus alpha-ketoglutarate or malate by about 80%. When succinate, an FAD-dependent oxidation, was used as a substrate, oxygen consumption was not inhibited by DBCP. It is concluded that DBCP inhibits sperm carbohydrate metabolism at the NADH dehydrogenase step in the mitochondrial electron transport chain.

Animals↗
PubMed2005

Atropine-induced inhibition of sperm and semen transport impairs fertility in male rats.

Previous studies revealed that atropine reduced male fertility in rats without any effects on mating performance, sperm production and motility, and testicular morphology. The present study was conducted to investigate whether the impairment of male fertility induced by atropine was related to the inhibition of sperm and semen transports from the vas deferens and seminal vesicle to the urethra during the process of emission. Male rats were treated with atropine at 125 mg/kg/day for 10-17 days prior to mating with untreated females. After confirmation of mating, male rats were euthanized and sperm number in the vas deferens and weights of the seminal vesicle and copulatory plug were determined as indicators of inhibition of sperm and semen transports, respectively. Reproductive status of mated females was determined on gestation days 15-17. A low pregnancy rate associated with a decreased number of implants was observed in females that mated with the atropine-treated males. The average number of sperm in the vas deferens was increased in the atropine-treated males. The average seminal vesicle weight in the atropine-treated males was greater than that of controls. The copulatory plug weights were decreased in the atropine-treated males. These results suggest that inhibitions of sperm and semen transports from the vas deferens and seminal vesicle to the urethra during the process of emission result in reduced male fertility in rats.

Administration, Oral↗
PubMed1994

Male contraception: hormonal, mechanical and other.

Methods of male contraception that have been developed so far have mainly focused on the inhibition of spermatogenesis through suppression of the hypothalamo-pituitary secretion of gonadotrophins, and simultaneous supplementation with androgens. These methods include the use of combinations of progestogens or luteinizing hormone-releasing hormone antagonists and testosterone derivatives, or high dose testosterone. Though effective contraception can be obtained, side-effects and/or the high cost of treatment limit the widespread use of these approaches. Inhibition of sperm maturation in the epididymis, or direct interference with spermatogenic cells or the cells of Sertoli by e.g. gossypol have been abandoned because of toxic side-effects. Voluntary sterilization by vasectomy is the most commonly used method of male contraception, but its surgical nature, problematic reversibility and suspected link with subsequent prostate cancer render the method far from ideal. Non-surgical vas occlusion may overcome some of these problems, but data on long-term side-effects and reversibility are lacking. New contraceptive developments should focus on interfering with highly specific aspects of spermatogenesis such as unique enzymatic processes and intercellular communication through cytokines, or application of antibodies against antigens of the epididymis or the spermatozoa. Only through better understanding of normal and pathological spermatogenesis will it be possible to develop an acceptable male contraceptive.

Contraception↗
PubMedDate not supplied

Spermicidal activity of some halides.

Though most of the metallic ions are spermicidal in action, the present investigation emphasises the spermicidal activity of anions. Among the inorganic compounds screened at 4 concentrations (0.01%, 0.1%, 1% and 5%) halides are mainly spermicidal, except NaCl, KCl & CsCl which are spermiostatic; sulphates and nitrates are mainly spermiostatic except ZnSO4 at 1% concentration and above; CuSO4, Al2 (SO4)3, Uo2(NO3)2.6H2O and AgNO3 at 5% concentration where they become spermicidal.

Adult↗
PubMed1986

Spermicidal effect in vitro by the active principle of garlic.

The in vitro spermicidal effect of Allitridum, an active principle of garlic, was investigated. The data showed that sperm motility was inhibited with various concentrations of Allitridum at different intervals ranging from 20 seconds-200 minutes as compared to control. An obvious immobilization of spermatozoa occurred at 7.5 mg/ml of Allitridum. The effects on sperm motility appeared to be dose-dependent.

Allyl Compounds↗
PubMed1986

Effects of gossypol on human and monkey sperm motility in vitro.

The effects of gossypol acetic acid on human and monkey sperm motility in vitro were studied by using multiexposure photography technique. Human and monkey spermatozoa were inhibited by gossypol to different degrees. Monkey sperm were absolutely immotile within 15 min after 50 microM of gossypol was added, but motility of human spermatozoa was not completely suppressed by gossypol even at the highest concentration used and longest duration of exposure.

Animals↗
PubMed1983

Mitochondrial respiration inhibitors and human sperm motility: implication in the development of spermicides.

Three inhibitors of the mitochondrial respiratory chain, rotenone, antimycin A, potassium cyanide and the uncoupler of oxidative phosphorylation, 2,4-dinitrophenol, were tested for their sperm immobilizing effects with a trans-membrane migration method. None of these drugs inhibited human sperm motility at the concentrations of 10(-6), 10(-5), 10(-4) and 10(-3) M. The suggestion to develop spermicidal contraceptives from mitochondrial respiration inhibitors could not be substantiated; and the theory that motility inhibiting drugs act primarily on the sperm membrane was reconfirmed.

Antimycin A↗
PubMed1984

Glutathione and caffeine antagonize the sperm-immobilizing effect of a vaginal contraceptive.

The concentration-dependent inhibition of Neosampoon, a vaginal contraceptive, on ejaculated human sperm motility was studied with a transmembrane migration method. Caffeine (5mM), glutathione (5mM) and glutathione (15mM) all reactivated the motility of Neosampoon-immobilized sperm. Caffeine (5mM) was more potent than glutathione in antagonizing Neosampoon; there was no difference between the potency of 5mM- and 15mM-glutathione. Human sperm motility could be a model for studying the interaction of membrane-active drugs, including the protective effect of glutathione against membrane-disrupting agents.

Caffeine↗