Showing papers on "Sperm motility published in 1984"

Development of an assay to assess the functional integrity of the human sperm membrane and its relationship to other semen characteristics

Abstract: The objective of this study was to develop a relatively simple test to evaluate the functional integrity of the membranes of human spermatozoa. As in some other species, human spermatozoa 'swell' under hypo-osmotic conditions due to the influx of water and the expansion of the membranes. A mixture of equal parts of fructose and sodium citrate (150 mosmol) with calculated ionic strength of 0.15 resulted in a maximal number of clearly identifiable swollen spermatozoa. Only small variations were seen when different aliquants of the same semen samples were separately evaluated. A high correlation (r = 0.94) was obtained between expected and observed values of swollen spermatozoa when known amounts of heat-treated spermatozoa, unable to undergo swelling, were added to untreated spermatozoa. A good correlation (r = 0.90) was also observed between the % spermatozoa in a semen sample that were capable of undergoing swelling and the % of denuded hamster oocytes that were penetrated by capacitated spermatozoa from the same semen sample. By contrast, the correlations between % sperm swelling in ejaculates and % normal sperm forms, % motile spermatozoa and % spermatozoa that do not stain with eosin-Y (supravital stain) in the same ejaculates were 0.30, 0.61 and 0.52, respectively. Therefore, the hypoosmotic swelling technique to evaluate the functional integrity of the sperm membrane appears to give high repeatability and accuracy and is closely correlated to the in-vitro fertilizing ability of spermatozoa. It may be a useful addition to the standard semen analysis.

Characterization of hyperactivated motility by human spermatozoa during capacitation: comparison of fertile and oligozoospermic sperm populations.

Abstract: Suspensions of capacitating human spermatozoa were analyzed for potential hyperactivated movements using videomicrographic methods. Analysis was carried out on aliquots of 22 sperm suspensions, which were proved fertile several hours later during human in vitro fertilization. After approximately 3 h of capacitation, 22.1% of the fertile spermatozoa displayed motility patterns designated as hyperactivated. Over 80% of these hyperactivated spermatozoa moved with a wide-amplitude, two-dimensional whiplash pattern, displaying marked lateral displacement of the head. Only 8.4% of capacitating spermatozoa from oligozoospermic patients showed these hyperactivated movements. The incidence of hyperactivated movements by fertile and oligozoospermic spermatozoa could be significantly increased after exposure to various motility stimulants. The clinical significance of hyperactivation as a functional assay of fertilizing capacity is discussed.

Inhibition of bovine spermatozoa by caudal epididymal fluid: II. Interaction of pH and a quiescence factor.

Abstract: Previous studies (Carr and Acott , 1984) indicate that bovine sperm are maintained in a quiescent state in the caudal epididymis (CE) by a pH-dependent inhibitory factor. Here, we have determined that the pH of bovine CE fluid and of CE semen is approximately 5.8, and that the motility of CE sperm in undiluted CE fluid increases as the pH is elevated. Therefore, the acidity of CE fluid may play a physiological role in the maintenance of sperm quiescence. The changes in sperm motility, in response to changes in the pH of CE fluid, are reversible and rapid. Dilution of CE fluid with buffers at either pH 5.5 or 7.6 produces a much slower initiation of motility. In buffer a significantly lower pH is required to inhibit sperm motility than is required in CE fluid. The apparent pKs for inhibition are 5.3 in buffer and 6.6 in CE fluid. However, the motility of sperm in buffers that contain lactate, shows a pH dependence similar to sperm in CE fluid. That is, lactate inactivates sperm in buffer at pH 5.5 but not at pH 7.6. Lactate, and several other permeant weak acids, have previously been shown to reduce the intracellular pH of bovine sperm and many other types of cells. We show that these permeant weak acids, but not impermeant weak acids, reversibly reduce CE sperm motility in buffer at pH 5.5 but not at pH 7.6. Weak bases, which have previously been shown to elevate intracellular pH, initiate sperm motility in CE fluid. These results suggest that intracellular pH can regulate CE sperm motility and may be the intracellular messenger for the pH-dependent quiescence factor. Although sperm cyclic AMP levels have been previously correlated with motility stimulation, cyclic AMP levels do not change when the pH of CE fluid is elevated, even though full motility is initiated.

Lipid peroxidation and the reactions of superoxide and hydrogen peroxide in mouse spermatozoa.

Abstract: Mouse spermatozoa released from the cauda epididymidis underwent spontaneous lipid peroxidation during aerobic incubation at 37 degrees C in medium containing 113 mM NaCl, 0.4 mM EDTA, and 15 mM sodium phosphate ( NTPC ). The rate of lipid peroxidation, as measured by malonaldehyde production, was 0.045 nmol malonaldehyde/h per 10(3) cells. The motility of these cells declined with time in medium NTPC ; the percent spermatozoa showing no motility increased linearly with production of malonaldehyde. All flagellar activity stopped at 0.80 nmol malonaldehyde/10(8) cells, independent of the malonaldehyde production rate. Spermatozoa suspended in NTPC at 24 degrees C produced O(2), with an intrinsic rate of 1.96 nmol/min per 10(8) cells; this increased to 3.80 nmol/min per 10(8) cells in 10 mM cyanide. Mouse sperm contain 3.5 U/10(8) cells of superoxide dismutase activity, 91% of which is sensitive, and 9% of which is insensitive, to cyanide inhibition. Mouse sperm also produce H2O2, all of which can be attributed to the action of superoxide dismutase on O(2) produced. Mouse sperm contain high levels of glutathione and of glutathione reductase and peroxidase activities, implicating the glutathione system as the major protective enzyme system against cell damage by autoxidation. This is in contrast to rabbit spermatozoa, which have little endogenous glutathione and rely on superoxide dismutase as protective enzyme against peroxidative damage.

Stimulation of rhesus monkey sperm capacitation by cyclic nucleotide mediators

Abstract: Capacitation of rhesus monkey spermatozoa was assessed by monitoring sperm flagellar beat and trajectory changes during incubation in vitro and by determining sperm penetration into rhesus oocytes and hamster zona-free ova. Rhesus sperm capacitation in vitro depended on the addition to the culture medium of the cyclic nucleotide mediators, caffeine and dibutyryl cyclic AMP. Capacitation was correlated with the development of hyperactivated motility. Spermatozoa treated with the cyclic nucleotide mediators, and showing hyperactivated motility, penetrated 57.4% of all rhesus oocytes and fertilized 88.9% of mature rhesus oocytes that were morphologically normal. Control spermatozoa did not penetrate any of the eggs. Some sperm penetration into hamster ova occurred but was not statistically significant. These data provide a basis for achieving in-vitro fertilization in the rhesus monkey and information on specific sperm motility characteristics associated with fertilizing ability.

Analysis of human sperm function following exposure to the ionophore A23187. Comparison of normospermic and oligozoospermic men.

Abstract: Time exposure photomicrography and interspecific in vitro fertilization techniques have been used to compare the responses to the divalent cation ionophore A23187 of spermatozoa from normal fertile and oligozoospermic men. The fertilizing capacity of spermatozoa from the fertile controls produced a bell-shaped dose response curve when assessed in the presence of ionophore. The optimal responses occurred in the presence of 50 and 100 microM A23187. At this concentration, a mean penetration rate of about 75%, in association with multiple polyspermy, was observed without significant changes in motility patterns. At higher doses of A23187, there was a decline in fertilization rates, an independent reduction in sperm motility, and a significant decrease in the amplitude of lateral sperm head displacement. In contrast to the fertile controls, spermatozoa recovered from patients with oligozoospermia failed to exhibit a significant change in their fertilizing potential following exposure to A23187. Calculations based on the Poisson distribution theory indicated that this lack of responsiveness was not related to any differences in the motility of the spermatozoa from the oligozoospermic patients compared to the controls. These results suggest that calcium ionophores may be of value in providing a rapid and sensitive indicator of the functional competence of human spermatozoa, which circumvents problems concerning the rate and efficiency of sperm capacitation encountered with conventional protocols.

Testicular function in potential sperm donors: normal ranges and the effects of smoking and varicocele.

Abstract: Testicular exocrine (semen analysis) and endocrine (plasma LH, FSH, prolactin and testosterone) function was assessed in 119 consecutive healthy men presenting for screening as potential sperm donors Since these volunteers were unbiased with respect to their fertility status, this sample of the general male population was suitable to determine normal ranges and the influence of a variety of physical (height, weight, standardized body weight, varicocele) and demographic (age, marital and fertility status, tobacco and alcohol consumption) factors on normal human testicular endocrine and exocrine function, without the confounding effects of bias in selection of subjects The statistical distribution of all seminal parameters was non-gaussian, but cube-root transformation of the data normalized the distribution, allowing for parametric statistical analysis The median (and 95% confidence limits) for the various semen parameters was 730 (106-2353) million sperm per ml; 1890 (126-868) million sperm per ejaculate; 504 (59-1819) million motile sperm per ml; 1330 (69-6617) million motile sperm per ejaculate; 540 (70-1729) million morphologically normal sperm per ml and 1385 (75-672) million morphologically normal sperm per ejaculate Testicular volume was correlated positively with measures of physique such as standardized body weight (r = 025, P less than 001) and body surface area (r = 030, P less than 0002), and negatively with plasma levels of FSH (r = -031), P less than 0002) but not LH Sperm output was positively correlated with testicular volume (r = 028, P less than 0005) and negatively correlated with plasma FSH (r = -031, P less than 0002) and plasma LH (r = -031, P less than 0002) Smoking was associated with a highly significant reduction in sperm output and motility Men with varicocele (25%) were significantly taller, had slightly lower haemoglobin levels and moderate left (but not right) testicular atrophy, but neither seminal nor hormonal parameters were different from men without varicocele There was no difference in any markers of human testicular function between men according to marital or fertility status, grades of moderate alcohol consumption or the presence of low titres of sperm antibodies

Sperm concentration and the fertilization of human eggs in vitro.

Abstract: The effect of sperm concentration on the fertilization of preovulatory and immature human eggs was studied in the context of an ongoing in vitro fertilization-embryo transfer (IVF-ET) program. Fertilization success was independent of the follicular recruitment protocol used, and with preovulatory eggs, was inversely related to sperm concentration over the range of 2.5 - 50 X 10(4) motile sperm/ml. Maximum fertilization (80.8%) occurred at a concentration of 2.5 X 10(4) motile sperm/ml. The incidence of polyspermic fertilization was directly related to the sperm concentration, decreasing from 5.5% at 10 X 10(4) to 0% at 1-2.5 X 10(4) motile sperm/ml. Immature eggs cultured in vitro, then inseminated, also demonstrated an inverse relationship between fertilization and sperm concentration with a maximum fertilization rate of 66.6% at 5 X 10(4) motile sperm/ml. The percentage of motile sperm in the inseminating population had no influence on fertilization rates unless the value dropped below 40%. Fertilization success using sperm from oligospermic and polyzoospermic males was also examined. In contrast to males with normal semen parameters, oligospermic males demonstrated highest fertilization success at 50 X 10(4) motile sperm/ml. The IVF of preovulatory eggs using sperm from polyzoospermic males was comparable to that for males with normal semen parameters at equivalent sperm concentrations. The implications of these findings to the application of IVF-ET technology to the infertile couple is discussed.

Assessment and Preparation of Semen for In Vitro Fertilization

Abstract: This chapter details a successful method for obtaining highly motile spermatozoa from human semen for in vitro fertilization Background studies, areas of uncertainty which require further investigation and the possibility of using IVF as a method of treatment for infertility due to poor semen quality are also mentioned

Effects of lipid peroxide formation in fowl semen on sperm motility, ATP content and fertilizing ability

Abstract: The ability of samples of semen from individual male fowl to form the products of lipid peroxidation during 5 h aerobic incubation at 40 degrees C varied between 0 and 8 nmol malonaldehyde/10(9) spermatozoa. Formation of higher concentrations of malonaldehyde was associated with a partial or complete loss of fertilizing ability whilst the fertilizing ability of samples producing low or negligible concentrations of malonaldehyde remained unimpaired. The semen of birds which showed a tendency to form high concentrations of malonaldehyde was not readily identifiable as abnormal by assessment of sperm motility, morphology or ATP content. Nor was the loss of fertilizing ability during aerobic incubation associated with an obvious change in these characteristics.

Identification of epidermal growth factor-like activity in human male reproductive tissues and fluids.

Abstract: Epidermal growth factor-like activity (EGF-LA) has been detected in human seminal plasma in concentrations of 5–150 ngeq/ml (36.4 ± 2.1, mean ± SEM), using a heterologous RRA with murine EGF. The samples were obtained from normal, subfertile and azoospermic men, aged 21–50 yr. No correlation was found between EGF concentration and age of donor, sperm count, sperm motility, or period of sexual abstinence before sample collection. High performance liquid chromatography of the seminal plasma resulted in a main peak of EGF-LA which eluted at 29% acetonitrile, compared to 33% for murine EGF. Microsomal membranes were prepared from several tissues from the human male reproductive tract and were tested for their ability to bind radioiodinated murine EGF. Specific EGF binding activity was detectable in testicular membrane preparations but was not detectable in membranes prepared from human prostate, seminal vesicle, epididymis, or spermatozoa. Endogenous EGF-LA was detectable in human testis, seminal vesicle, pro...

Inhibition of bovine spermatozoa by caudal epididymal fluid: I. Studies of a sperm motility quiescence factor.

Abstract: Spermatozoa from all portions of the bovine epididymis are essentially quiescent when examined in vitro without dilution However, sperm from the caudal epididymis, particularly the distal portion, develop full motility when they are diluted into seminal plasma or simple isotonic buffers Dilution of the sperm into neat cauda epididymal fluid (CE fluid) does not result in the initiation of motility The initiation of motility upon dilution into buffers is complete within 10-20 min, while the inhibition induced by CE fluid is nearly instantaneous CE fluid concentration, but not sperm concentration, controls sperm motility Therefore, an inhibitory component of this fluid, but not sperm-sperm interactions, is responsible for the inhibition CE sperm, which have been diluted into isotonic buffers and are consequently motile, become quiescent when resuspended in CE fluid; thus, this process is fully reversible No elevations in sperm cyclic AMP levels can be detected concomitant with the induction of motility but high concentrations of cyclic AMP phosphodiesterase inhibitors can overcome the quiescence induced by CE fluid The inhibitors of CE sperm motility reported for other species, eg, the high-viscosity mucin, immobilin ; carnitine; calcium; or glycerylphosphorylcholine , do not appear to be of importance in the bovine caudal epididymis The quiescence produced by bovine CE fluid is strongly dependent upon the extracellular pH; ie, motility is inhibited at pH 55 but not at pH 76

The onset and maintenance of hyperactivated motility of spermatozoa from the mouse

Abstract: Estimates were made of the proportion of freely motile mouse spermatozoa displaying hyperactivated motility by an objective photographic method employing stroboscopic illumination under dark-field conditions and examining displacements of the sperm head and bend angles of the sperm tail. In media known to support in vitro fertilisation hyperactivation gradually appeared reaching about 40% by 6 hr incubation, and it was not promoted by 2 mM caffeine or 0.1 mM Bt2 cAMP or washing the cells free of epididymal fluid. Raising the osmolarity of the medium to 400 mOSM with electrolytes, but not nonelectrolytes, did promote hyperactivation (60% by 2 hr) suggesting that the ionic strength of the medium was important. Hyperactivation in high ionic strength media could be prevented by removing or chelating Ca2+, or replacing Ca2+ with Ba2+ or Mg2+, when nonhyperactivated motility was maintained, but Sr2+, like Ca2+, permitted hyperactivated motility. Hyperactivation in low ionic strength medium could be promoted by the ionophore A23187, suggesting that Ca2+ movement into the cells is important. Of a range of glycolytic substrates tested supporting nonhyperactivated motility in the presence of lactate, only glucose supported hyperactivation. Addition to glucose— or Ca2+ — free, high ionic strength media after 2 hr increased hyperactivation immediately (glucose) or after a lag of 2 hr (Ca2+) suggesting that glucose acts on a Ca2+ — primed system. Removal from high ionic strength medium, chelation of Ca2+ or inhibition of glucose metabolism did not prevent hyperactivation continuing once it had been initiated, indicating different requirements for initiation and maintenance of this form of motility.

Stimulation of sperm respiration rates by speract and resact at alkaline extracellular pH.

Abstract: At an extracellular pH of 6.6, a peptide (resact) isolated from the egg jelly of Arbacia punctulata increased the respiration rates of A. punctulata spermatozoa but did not activate sperm cells from Lytechinus pictus. In contrast, speract (Gly-Phe-Asp-Leu-Asn-Gly-Gly-Gly-Val-Gly), elevated the respiration rates of L. pictus but not A. punctulata spermatozoa. At normal seawater pH (7.6-8.0) egg jelly from A. punctulata, or egg jelly from L. pictus purified free of speract, inhibited L. pictus sperm respiration rates. Similarly, the egg jelly from L. pictus inhibited the respiration rates of A. punctulata spermatozoa. The jelly component responsible for the inhibition of respiration was nondialyzable. The inhibition of respiration induced by jelly could be reversed by the addition of speract to L. pictus spermatozoa and by the addition of resact to A. punctulata spermatozoa. Speract stimulated L. pictus sperm respiration half-maximally at about 1 nM in the presence of either heterologous or homologous (speract-free) jelly. Monensin A, an ionophore which elevates sperm intracellular pH, reversed the jelly inhibition of respiration. These results demonstrate that two peptides associated with eggs (speract and resact) can stimulate sperm motility and metabolism in the face of inhibitory components present in the egg jelly. Additionally, the peptides demonstrate species specificity.

Effects of an LHRH agonist analog upon sexual function in male dogs. Suppression, reversibility, and effect of testosterone replacement.

Abstract: Male beagle dogs were injected once daily with 10 micrograms/kg of [6-D-(2-naphthyl)alanine]-LHRH (D-Nal(2)6-LHRH), a potent LHRH agonist, for periods up to 42 days, with recovery periods up to 172 days. Blood samples collected at regular intervals were assayed for LH, FSH, and testosterone; total ejaculates were collected and analyzed weekly, and animals were sacrificed at various intervals for sex organ weights and histology. The first injection of D-Nal(2)6-LHRH caused an acute elevation in plasma levels of LH, FSH, and testosterone, measured at 2 and 4 hours after the injection. This acute response to injection was attenuated with each successive injection and by two weeks no elevation was seen, suggesting a down-regulation of pituitary response. Basal levels of LH and testosterone were maximally depressed by four days of treatment. Testis volume, duration of erection, ejaculate volume, sperm count, sperm motility and testis volume all declined during treatment, with sperm count significantly lowered by two weeks and ejaculation volume becoming zero by five weeks of treatment. Spermatogenesis, assessed histologically, was partially suppressed at ten days and completely suppressed by 38 days of treatment. All parameters returned to normal following cessation of treatment. Recovery time was longer for the dogs treated for 42 days than for those treated for ten days. When testosterone was supplemented during 42 days of agonist treatment, basal plasma testosterone levels were maintained at the low end of the normal range. Testosterone supplementation did not prevent pituitary down-regulation, suppression of spermatogenesis, or the decrease in testis and epididymis weights, but prevented the decline in duration of erection. Ejaculate volume and sperm count declined more slowly with combination treatment than with agonist alone. During the decline in sperm count sperm motility was maintained with combination treatment. Injection of hCG into control and agonist treated dogs resulted in similar percentage increases in plasma levels of testosterone, although peak levels were greater in control than in treated animals. The data suggest a pituitary desensitization with this LHRH agonist in the dog but only a minor role for testicular desensitization.

Human sperm motility after migration into, and incubation in, synthetic media

Abstract: Ten frames/sec microcinematography (“film”), 1 second timed-exposure photomicrography (“photo”), and laser Doppler velocimetry (LDV) were used to analyse the swimming patterns of human spermatozoa after migration (1 h at 37°C) into an overlying layer of either BWW or Menezo's B2 media. The upper layer of medium was carefully removed and further incubated at 37°C for either 4 h (B2) or 5 h (BWW) and the sperm motility analysed again. Five experiments were performed using semen from different donors. Film and photo analyses gave the relative incidence of nonprogressive and progressively motile spermatozoa plus, for the progressive spermatozoa, the velocities of progression (Vp) and amplitudes of lateral head displacement (Ah). LDV gave the percentage of motile spermatozoa and the modal instantaneous velocity (Vm). All postmigration sperm populations showed large significant increases in the percentage of motile spermatozoa, with good survival during incubation. The progressive postmigration spermatozoa generally moved with greater Vp and Ah than in the initial seminal plasma-diluted material; Vm was also increased. There were further increases in both Vp and Ah during incubation, but no change in Vm was detected. While the majority of spermatozoa were progressive, some showed a highly active pattern of movement which resulted in no net forward progression. The possible homology between these spermatozoa and the “hyperactivated” motility of capacitated spermatozoa in other mammalian species is discussed. Apparent discrepancies between the three methods used for motility analysis were seen, the possible causes and significances of which are also discussed.

Cyclic AMP-dependent activation of sea urchin and tunicate sperm motility.

Abstract: This report summarizes procedures that can be used to obtain high-quality reactivated motility of sperm flagella demembranated with Triton X-100. Although for years I have been reactivating sea urchin sperm flagella without exposing them to cyclic adenosine monophosphate (CAMP), the failure of these techniques to work with Ciona spermatozoa has led to the development of techniques involving incubation of demembranated spermatozoa with CAMP. This has led to the development of improved procedures for reactivating sea urchin spermatozoa, which give beat frequencies comparable to those of live spermatozoa. With both species, conditions can be found where a brief incubation with CAMP determines whether the spermatozoa are quiescent or fully motile when they are suspended in reactivation solution.

Stimulation of Sperm Production by Human Luteinizing Hormone in Gonadotropin-Suppressed Normal Men

Abstract: The relative roles of FSH and LH in the control of human spermatogenesis are not well established. We previously reported that supraphysiological doses of hCG can stimulate sperm production in gonadotropin-suppressed normal men despite prepubertal FSH levels. To determine whether more nearly physiological levels of human LH (hLH) also can stimulate spermatogenesis when FSH levels are suppressed, we administered hLH to normal men whose endogenous gonadotropin levels and sperm production were suppressed by exogenous testosterone enanthate (T). After a 3-month control period, 11 normal men received 200 mg T, im, weekly to suppress LH and FSH. T administration alone was continued for 3-4 months until 3 successive sperm concentrations (performed twice monthly) revealed azoospermia or severe oligospermia (sperm concentrations, less than 4 million/ml). Then, while continuing T, 4 of the 11 men (experimental subjects) simultaneously received 1100 IU hLH, sc, daily for 4-6 months to replace LH activity, leaving FSH activity suppressed. The effect on sperm production of the selective FSH deficiency produced by hLH plus T administration was determined. The remaining 7 men (control subjects) continued to receive T alone at the same dosage, without gonadotropin replacement, for an additional 6 months. In the four experimental subjects, sperm concentrations increased significantly from 0.7 +/- 0.7 million/ml (mean +/- SEM) during T treatment alone to 19 +/- 4 million/ml during hLH plus T administration (P less than 0.001). However, none of the men achieved sperm concentrations consistently in their own pretreatment range. Sperm motilities and morphologies were normal in all four subjects by the end of hLH plus T administration. In contrast, sperm concentrations in the seven control subjects remained suppressed (less than 3 million/ml) throughout the entire period of prolonged T administration alone. Serum LH bioactivity, determined monthly by in vitro mouse Leydig cell bioassay in all four experimental subjects, was markedly suppressed during T administration alone (120 +/- 10 ng/ml) compared to that during the control period (390 +/- 20 ng/ml; P less than 0.001). With the addition of hLH to T, LH bioactivity returned to control levels (400 +/- 40 ng/ml; P = NS compared to control value). Serum FSH levels determined monthly by RIA were reduced from 98 +/- 12 ng/ml during the control period to undetectable levels (less than 25 ng/ml) during the T alone and the hLH plus T periods (P less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)

Changes in motility that accompany the acrosome reaction in hyperactivated hamster spermatozoa

Abstract: High-speed videomicrography was used to compare the movement characteristics of hamster epididymal sperm which completed the acrosome reaction in vitro with those of unreacted sperm in the same sample. More than 90% of the motile sperm incubated for 4.25 hr in a modified Tyrode's medium containing bovine serum albumin, taurine, and epinephrine were hyperactivated and about half were acrosome reacted. The flagella of reacted sperm beat with significantly lower frequency and bent into more acute curves than those of unreacted sperm. Lowered beat frequencies were not attributable to aging, because sperm induced to react synchronously at 3.5 hr using lysophosphatidyl choline beat with similar lowered frequencies. Both acrosome-reacted and unreacted hyperactivated sperm swam in circular trajectories resulting from asymmetrical flagellar beating. The flagellar beating of unreacted sperm was more symmetrical; consequently, they swam in larger circles and had the potential to cover space more rapidly. Some unreacted sperm, perhaps in transition towards hyperactivation, swam in helical trajectories. When preincubated sperm were added to slides containing oocytes in cumulus, some unreacted sperm initiated cumulus penetration. All reacted sperm failed to do so, adhering instead to the cumulus at its boundary. Reacted sperm attached to the zonae pellucidae of cumulus-free oocytes via the region of the inner acrosomal membrane. Unreacted sperm attached via the equatorial region, but pivoted about the point of attachment, thus failing to generate sustained thrust against the zona. In conclusion, unreacted hyperactivated sperm have a different potential than reacted sperm for movement and interaction with egg vestments.

The Effect of a Single Sauna Exposure on Spermatozoa

Abstract: Semen was collected at weekly intervals for 3 wk before and 10 wk after the sauna exposure at 85°C for 20 minutes. The numbers, morphology, ultrastructure, motility, viability and metabolism of the sperm was assessed. Sperm numbers fell within one wk and slowly returned to normal in 5 wk. The earliest ultrastructural change was swelling of the plasma membrane, followed by an increase in the number of immature forms and disorganization of the arrangement of the mitochondria. Motility, glucose utilization and lactic acid accumulation of the sperm rose temporarily immediately after sauna.

Comparison of glycerol and a zwitter ion buffer system as cryoprotective media for human spermatozoa. Effect on motility, penetration of zona-free hamster oocytes, and acrosin/proacrosin

Abstract: This study compared the cryoprotective effect of glycerol with that of a zwitter ion buffer system (TESTCY). Spermatozoa that are cryopreserved in the presence of glycerol possess a somewhat higher progressive motility immediately after thawing than those preserved in the presence of TESTCY. However, after a 1-hour incubation in glycerol-free medium, the progressive motilities of the glycerol- and TESTCY-treated spermatozoa become essentially identical. After 2 hours in culture medium, TESTCY-treated spermatozoa possess a higher motility than glycerol-treated spermatozoa, indicating that TESTCY is a better preservative than glycerol for the long-term motility of human spermatozoa. The fertilizing potential of the cryopreserved spermatozoa was assessed by their ability to penetrate zona-free hamster oocytes in vitro. Spermatozoa that are cryopreserved in the presence of TESTCY produce three- to four-fold higher penetration rates than glycerol-treated, cryopreserved spermatozoa. Cryopreservation in the presence of TESTCY also results in a higher stability of the acrosin/proacrosin system than when the spermatozoa are preserved in glycerol, since about two- to three-fold higher levels of proacrosin are retained. These results indicate that TESTCY is a better cryopreservative for human spermatozoa than glycerol.