Effects of (H + ), (Na + ), (K + ) and certain membrane-active drugs on glycolysis, motility, and ATP synthesis by human spermatozoa

The Potential Relationship Between Different Human Female Reproductive Disorders and Sperm Quality in Female Genital Tract

Spermatozoa should travel throughout the female reproductive tract to reach its ultimate goal, fertilization of the oocyte. At the ejaculation moment, millions of sperm within a few milliliters of the ejaculate are deposited at the cranial segment of vagina and make their journey to the fertilization site. This is done by means of various factors, such as sperm motility, the uterine and fallopian tubes contractility, and the ciliary movement of the lining cells. During this migration, spermatozoa interact with the female microenvironment both physically and molecularly. In this regard, the quality of the environmental conditions may affect this interaction. Therefore, some alterations in women's genital tract microenvironment, such as conditions that occur in female reproductive disorders, may have detrimental effects on sperm reproductive function. In this review, human sperm migration through the female tract is described, and the potential effects of different reproductive disorders at reproductive organs, such as vagina, uterine cervix, uterus, fallopian tubes, and ovary on sperm survival and quality, are also argued. The understanding of those conditions that may impair sperm fertility in the female genital tract can provide a more accurate diagnosis of the causes of infertility in couples. This can ultimately lead to the discovery of effective treatment approaches.

Effects of extracellular potassium concentrations on acrosome reaction and polyspermy during in vitro fertilization and subsequent development in vitro in the pig

Potassium (K(+)) concentration in the mammalian oviduct and uterus is particularly interesting due to its unusually high concentration (12 to 25 mM) compared with that in the blood stream (3 to 6 mM). In this study we examined the effects of various K(+) concentrations in the fertilization medium on polyspermy and subsequent in vitro development of porcine oocytes. In the absence of K(+) in the fertilization medium, sperm penetration was not observed. The incidence of polyspermy was significantly higher in the fertilization medium that contained 6 or 12 mM K(+) as compared with 3 mM K(+). The mean number of sperm penetrated in oocytes in medium with 6 and 12 mM K(+) was higher than in medium with 3 mM K(+). The addition of 3, 6 or 12 mM K(+) to the fertilization medium did not significantly affect the proportion of zygotes that developed to the blastocyst stage (14.1, 12.4 and 15.0%, respectively). Chlorotetracycline (CTC) analysis was used to determine the capacitation and acrosome reaction of spermatozoa incubated for 3 h with various concentrations of K(+). The number of acrosome reacted spermatozoa decreased with increasing K(+) concentration. These results suggest that extracellular K(+) in the fertilization medium affects sperm acrosome reaction which may be related to the sperm penetration.

Complementary effects of propranolol and nonoxynol-9 upon human sperm motility

The inhibitory effects of nonoxynol-9, DL- and D-propranolol upon human sperm motility were determined in vitro. All three compounds were capable of causing complete cessation of sperm movement. However, greater efficacy was achieved using combinations of nonoxynol-9 and propranolol, suggesting a complementary interaction between these compounds. Investigations of the mechanism of action of propranolol revealed that an influx of calcium accompanied the loss of motility. However, since incubation in the absence of calcium enhanced the spermicidal effects of this compound, it was concluded that this calcium influx did not constitute the primary means by which motility was disrupted. Low doses of propranolol, which did not affect motility, were found to inhibit the capacity of human spermatozoa for sperm-oocyte fusion.

The effect of cocaine on sperm motility characteristics and bovine cervical mucus penetration

OBJECTIVES

To determine the in vitro effects of cocaine on sperm motility and bovine mucus penetration because cocaine abuse is associated with decreased sperm motility, and related compounds, such as procaine, are known to decrease sperm motility.

DESIGN

Human semen samples were exposed to a range of cocaine concentrations and the effects quantified using computer-assisted sperm analysis and the bovine mucus penetration test.

SETTING

University research laboratory.

PATIENTS, PARTICIPANTS

Samples were obtained from 18 healthy volunteers.

INTERVENTIONS

Normal semen samples were exposed to concentrations of cocaine ranging from 10(-11) to 10(-4) M. Motility characteristics were evaluated after 2 hours, and bovine mucus penetration was evaluated after 30 minutes, 1 hour, and 2 hours. Mucus penetration by washed sperm was also evaluated.

MAIN OUTCOME MEASURES

Motility characteristics were evaluated using computer-assisted sperm analysis, and functional sperm motility was evaluated using the bovine mucus penetration test.

RESULTS

Cocaine exposure decreased the percentage of motile sperm in a concentration-dependent manner with a maximum decrease of 23% at 10(-4) M but had no effect on other motility characteristics. Cocaine decreased bovine mucus penetration by 12% at high cocaine concentrations (10(-4) M), but increased penetration by 69% at low concentrations (10(-9) M). Washing sperm before cocaine exposure attenuated the increased sperm penetration.

CONCLUSION

The ability of cocaine to decrease the percentage of motile sperm at high concentrations may explain the decreased sperm motility associated with cocaine use. Cocaine's ability to augment sperm penetration at low concentrations suggests an interaction of cocaine with the sperm adrenergic system.

Effects of tetraphenylboron on the motility, oxygen consumption, and adenosine 5'-triphosphate content of fowl spermatozoa

The effects of tetraphenylboron on the motility and metabolism of fowl spermatozoa at 30 C were investigated. The motility of intact fowl spermatozoa was reduced by tetraphenylboron at concentrations that had little effect on the oxygen consumption and adenosine 5'-triphosphate content of spermatozoa. The inhibition of motility was reversed by the removal of tetraphenylboron. Furthermore, the addition of tetraphenylboron improved the maintenance of spermatozoa during storage. Tetraphenylboron did not affect the motility of demembraned spermatozoa, suggesting that the locus of action of tetraphenylboron is not directly on the axoneme of fowl spermatozoa.

Comparative effects of (+)-propranolol and nonoxynol-9 on human sperm motility in-vitro

Using the modified transmembrane migration method to measure sperm motility, it was shown that the surfactant nonoxynol-9 alone, was twice as potent as (+)-propranolol alone as a spermicidal agent. Addition of (+)-propranolol to nonoxynol-9 shifted the dose-response curve to the left of the curves for either component alone, and a surprising synergistic action was evident. These observations may form the basis for the development of a new advantageous topical contraceptive combination product.

Beta-adrenoceptor antagonists and human sperm motility

Several beta-adrenoceptor blocking agents have been evaluated for spermicidal activity using a transmembrane migration method. The rank order of potency of the active compounds was: penbutolol greater than (+)-propranolol greater than bufuralol greater than (-)-alprenolol greater than oxprenolol greater than metoprolol. Atenolol, pindolol, practolol, tolamolol were without activity. The observed potencies of spermicidal activity are believed to be unrelated to beta-blocking activities, and we have shown that whilst they are not predictable from lipid solubility or nonspecific membrane properties of the compound alone, both these aspects appear to play a role in this pharmacological activity.

Concentration of D-propranolol in cervico-vaginal mucus: targeting of a novel spermicide

It may be possible to develop new contraceptives that can be administered by mouth and will exert their effects after concentration in cervico-vaginal mucus. D-Propranolol was administered in 80 mg doses by mouth to six healthy female volunteers. Samples of blood plasma and cervico-vaginal mucus were obtained before and on six occasions up to 24 hours after drug ingestion. D-Propranolol was concentrated in cervico-vaginal mucus. No changes in blood pressure, pulse, or forced expiratory peak flow (FEPF) were observed.

Effect of reserpine on fertilizing capacity of human spermatozoa

The effect of reserpine at various concentrations (2 X 10(-6), 2 X 10(-7), 2 X 10(-8), 2 X 10(-9) and 2 X 10(-10) M) on the in vitro fertilizing capacity of human spermatozoa was studied. Spermatozoa collected from presumably fertile men were washed in BWW medium and incubated with different concentrations of reserpine for 5 hr before insemination of the zona-free hamster ova. The spermatozoal penetration of the zona-free hamster ova was scored 6 hr later and the results were analyzed statistically. Reserpine, at all the concentrations tested, caused a significant dose-dependent decrease in the penetration of the denuded hamster ova in comparison to the control (p less than 0.05). The percent motility of spermatozoa decreased as a function of time during the preincubation period to initiate spermatozoal capacitation but there were no significant differences in the values between the control and the reserpine - treated spermatozoa (p greater than 0.05). These findings indicate that reserpine can affect the fertilizing capacity of human spermatozoa in vitro and provide an additional evidence to suggest the prospective use of reserpine as a vaginal contraceptive.

Propranolol concentrations in blood serum, seminal plasma and saliva in man after a single oral dose

A single dose of 80 mg racemic propranolol hydrochloride was administered by mouth to six healthy male volunteers. The mean concentration achieved in seminal plasma at 2 h after dosing was almost identical to that in blood serum. The concentrations of propranolol in seminal plasma and saliva were much less than those known to reduce sperm motility by 50% in vitro. The concentrations in saliva did not reflect those in blood serum. Propranolol in the dose administered in this study is unlikely to affect fertility by its presence in saliva or semen.

Effect of the membrane active ionophore, nigericin, on motility of ram spermatozoa

Ram spermatozoa diluted in Ringer-fructose-phosphate to a concentration of 5 X 10(6) cells/ml, were exposed to continuous variations of pH, using HCl or NaOH. Percent of motility and ATP level were measured within 1-2 min from the pH change. High percent of motility was observed in the range of 2 pH units, between pH 6.5 to 8.5, regardless of the source of the ATP production: mitochondria, fructolysis, or both. In the presence of nigericin (H +/K+ exchanger), two peaks of high motility were observed: one at alkaline pH (7.8-8.3) and the other at acidic pH (6.5-7.0). When nigericin was added to cells inhibited by 2-deoxyglucose (possessing mainly mitochondrial motility), the high percent of motility was noted at the alkaline pH (7.2-7.6). However, when nigericin was added to cells inhibited by Antimycin-A (possessing mainly fructolytic motility), the high percent of motility was observed at the acid pH (6.0-6.7). The ATP level was correlated with the pattern of the motility.

Propranolol as a novel, effective spermicide: preliminary findings

The efficacy and tolerability of 80 mg propranolol tablets as a vaginal contraceptive were studied in 198 fertile women for 11 months. The calculated one year life table pregnancy rate was 3.4/100 women and the Pearl index was 3.9/100 women years. No major adverse effects were encountered. The findings suggested that propranolol is an effective vaginal contraceptive whose failure rate compares favourably with that of other methods of contraception. Further study of propranolol and similar compounds is warranted.

Propranolol concentrations in plasma after insertion into the vagina

Six healthy women participated in a study of the concentrations of propranolol achieved in plasma after insertion of the drug into the vagina. In four of the women the concentrations were also determined after administration by mouth. The area under the concentration curve for propranolol administered per vaginam was significantly greater than that after oral administration. There were small significant reduction in systolic blood pressure, pulse rate, and forced expiratory volume in one second after vaginal administration but these did not cause any symptomatic side effects. The tolerability of the vagina to drugs and the safety of this form of treatment remain to be determined. Probably further studies of the contraceptive effects of propranolol should be conducted with the dextro isomer of the drug.

Influence of cations and albumin on human spermatozoa

The effects of potassium, calcium and magnesium cations, and albumin on motility of spermatozoa, were tested after 15 min, 4 hr, and 24 hr of incubation using laser Doppler velocimetry. The optimal concentration of K+ was found to be 11 mM; higher values decreased motility more severely than did lower ones, even when K+ was completely removed. Motility was increased in the presence of small amounts of calcium (from 0.8-1.7 mM) but was depressed by magnesium concentrations above 0.8 mM. Moderate concentrations of albumin (0.5-1%) improved motility, but the protecting effect of this compound--leading to a best sperm survival--appeared with higher concentrations (4%). In conclusion we observed that optimal ionic conditions presently found were corresponding well to the tubal environment in preovulatory phase.

Influence of lipid solubility on the sperm immobilizing effect of beta-adrenoceptor blocking drugs

1 Sperm immobilizing effects of five beta-adrenoceptor blockers were measured on six human semen samples with a trans-membrane migration method. 2 The concentrations which decreased sperm motility to 50% of control (ED50) were 0.8, 4.2, 6.2, 11.0 and 33.0 mM for propranolol, oxprenolol, metoprolol, acebutolol and sotalol respectively. 3 There was a linear correlation between the log values of ED50 and the log partition coefficients of these beta-adrenoceptor blockers. 4 Because the lipid solubility determines the sperm immobilizing potencies of beta-adrenoceptor blockers, we support the theory that beta-adrenoceptor blockers inhibit sperm motility by stabilizing the cellular membrane. 5 The clinical implication of this finding is that more lipid soluble drugs are likely to have more interference on sperm function, at least when they are used locally.

Investigations into the metabolism of human spermatozoa in relation to penetration capacity

Using a special chamber, the authors investigated the penetration capacity of spermatozoa of 120 sterile couples in both simple and crossed mucus penetration tests. Moreover, the glycolytic activity and the oxygen consumption of the ejaculates were biochemically determined in an artificial cervical mucus medium. A negative spermatozoan penetration was found to be associated with a markedly reduced aerobic glycolytic activity. It was for low-motility spermatozoa that no penetration was observed in cervical mucus, if the aerobic glycolysis was diminished, but the respiratory activity enhanced. Comparative investigations into the penetration capacity of spermatozoa in an artificial cervical mucus medium permit the detection of causes of male sterility, which exhibit metabolic regulation disturbances of spermatozoa.

Effects of ouabain on spermatozoan function: a review

The cardiac glycoside, ouabain, exerts its influence on spermatozoa by binding to and inhibiting Mg2+-activated Na+, K+-dependent ATPase that is located in the midpiece-tail membranes. Ouabain decreased intracellular potassium, increased intracellular sodium, and produced a biphasic and time-dependent effect on motility--stimulation at low concentrations and inhibition at high concentrations. The motility depression consisted of decreases in numbers of motile cells, percent progressive motility, beat frequency, and amplitude. Species differences and maturational age of the sperm cells were reflected in the degree of the ouabain effect and also the distribution of the ouabain-sensitive enzyme. The presence of this enzyme in spermatozoan membranes contributes significantly to regulation of sperm cell function through modulation of cationic fluxes which in "conventional" cell types influence their excitability.

Electrolyte concentration in semen

Sodium and Potassium ion concentrations were determined in the semen by the atomic absorption photometry technique in three groups of infertile patients and values were compared with those of a normal control group. Comparison showed that differences are not statistically significant. Also no correlation was established between the concentration of the two electrolytes in any of the studied groups, or between electrolyte concentration and sperm motility or density.

Adenosinetriphosphate (ATP) in human spermatozoa. II. Concentrations in fertile men

The Bucher's method was applied to establish normal values of ATP in the spermatozoa of fertile men. It was shown that the normal value is 6.5 +/- 0.34 S.E. microgram per 10(8) spermatozoa. Pools of spermatozoa showed that incubation in seminal plasma at room temperature produced a progressive loss of ATP in the gametes.

Effects of ions and K+:Na+ ratio on motility and oxygen consumption of human spermatozoa

Variations in the osmolarity of the medium altered motility, velocity, and oxygen consumption of human spermatozoa. Variations in the K+:Na+ ratio also altered their motility and velocity. These alterations, which reflect both the composition of the medium and individual characteristics of the donor, are discussed in relation to the diversity of milieu through which the sperm are transported.

Relationship of endogenous ATP to flagellar beat frequency in ejaculated bull spermatozoa

The relationship between endogenous ATP and flagellar beat frequency of bull spermatozoa was investigated using cinematographic and biochemical criteria. ATP content was measured by the luciferin-luciferase method. Potassium, sodium, chloride, and viscosity were used to alter motility to establish the concomitant effects on ATP content. Beat frequency was correlated to endogenous ATP in potassium-supplemented media. Increased sodium concentration was related to ATP content, but not to beat frequency. With increasing viscosity of the medium, the frequency of flagellary beat decreased dramatically, while ATP content of the cells remained unchanged.

Relationship between motility and the transport and binding of divalent cations to the plasma membrane of human spermatozoa

Measurements of fluorescence changes of the divalent cation probe chlortetracycline, which accumulates in the plasma membrane of human spermatozoa, and measurements of radioactive calcium uptake indicate that the plasma membrane of human spermatozoa is impermeable to calcium. Moreover, permeability to exogenous calcium is not changed when sperm motility is stimulated by agents which increase intracellular levels of adenosine 3':5'-monophosphate (cyclic AMP). Evidence is presented, however, which suggests that energy-dependent divalent cation binding to the plasma membrane is lowered when motility is increased by cyclic AMP phosphodiesterase inhibitors.

Movements of sodium and potassium into ejaculated boar spermatozoa suspended in seminal plasma and a biological salt solution

Uptake of 22Na and 42K into ejaculated boar spermatozoa was measured in vitro. Cells were suspended either in seminal plasma or in a biological salt solution of essentially the same composition as boar seminal plasma. Samples were incubated at 30 degrees C. Correction was made for extracellular space in the centrifuged sperm pellet. This was determined as 22Na-space, which was less (P less than 0.001) than [14C] carboxyinulin space. Large differences were observed among individual ejaculates. The half-time for potassium uptake into the spermatozoa averaged 11.5 min, which is much faster than that for leukocytes or erythrocytes. When the spermatozoa were suspended in the biological salt solution, the initial rate of 42K uptake was significantly decreased. This may be due to disturbances of the protein components of the sperm membrane. The uptake of 22Na into the spermatozoa was slow. Sodium and potassium transport appeared not to be coupled in the 3/2 ratio which has been reported for erythrocyte membranes. The average concentration of sodium was 108 mM in seminal plasma and 26 mM in the spermatozoa (112 mmol/kg water and 38 mmol/kg water, respectively). The corresponding figures for potassium were 26 mM and 51 mM (27 mmol/kg water and 74 mmol/kg water). The random error for a single determination for the various methods used varied between 2.4 and 13.3% of the mean.

The temperature, pH, and partial pressure of oxygen in the cervix and uterus of women and uterus of rats during the cycle

Changes in the temperature, pH, and partial pressure of oxygen (PO2) in the cervical canal and cavum uteri were measured in women with or without an intrauterine device and in the uteri of rats throughout the cycle. Only the PO2 exhibited significant variations, rising during the ovulatory phase in both cervices of women and uteri in rats. It is speculated that the rise in PO2 is related to the function of these organs as reservoirs for spermatozoa.