Changes in surface ATPase of rat spermatozoa in transit from the caput to the cauda epididymidis.

Rat spermatozoa from the cauda epididymidis were found to have a lower activity of the surface ATPase than the spermatozoa from the caput region. The enzyme from spermatozoa of both regions had the same Michaelis constant (Km) for ATP of 5 X 10(-4) M. It was partly inhibited by ouabain and fluoride, but strongly inhibited by Cu2+, Zn2+,p-chloromercuribenzoate, 8-anilino-1-naphthalenesulphonate Triton X-100, Lubrol-PX, urea, guanidine hydrochloride, sodium dodecyl sulphate and glycerylphosphorylcholine. The enzyme of the spermatozoa from the cauda epididymidis was more sensitive to inhibition by ouabain and fluoride but less sensitive to inhibition by Cu2+ than that of the cells form the caput region. The Arrhenius plot of the temperature dependence of enzymatic activity varied for the cells from the caput and cauda epididymidis. The differences in the enzyme properties of spermatozoa from the two regions of the epididymis suggested that the decline in the activity during epididymal maturation may reflect changes in the lipids and sulphydryl groups of the sperm membrane.     

Comparison between epididymosomes collected in the intraluminal compartment of the bovine caput and cauda epididymidis

During their transit along the epididymidis, mammalian spermatozoa acquire new proteins involved in the acquisition of male gamete fertilizing ability. We previously described membranous vesicles called epididymosomes, which are secreted in an apocrine manner by the epididymal epithelium. Some selected proteins associated with epididymosomes are transferred to spermatozoa during epididymal transit. The present study compared epididymosomes collected from caput epididymal fluid with vesicles from the cauda epididymidis in the bull. Two-dimensional gel electrophoresis revealed major differences in protein composition of epididymosomes isolated from the caput and cauda epididymidis. LC-QToF analysis of major protein spots as well as Western blot analysis confirmed the differences in proteins associated with these two populations of epididymosomes. Biotinylated proteins associated with caput and cauda epididymosomes also revealed differences. When incubated with caput epididymal spermatozoa, epididymosomes prepared from these two segments transferred different protein patterns. By contrast, cauda epididymosomes transferred the same pattern of proteins to spermatozoa from the caput and cauda epididymidis. Transfer of biotinylated proteins from cauda epididymosomes to caput spermatozoa decreased in a dose-dependent manner when biotinylated epididymosomes were diluted with unbiotinylated vesicles. Caput epididymosomes added in excess were unable to inhibit transfer of biotinylated proteins from cauda epididymosomes to caput spermatozoa. Following transfer of biotinylated proteins from cauda epididymosomes to caput spermatozoa, addition of unbiotinylated cauda epididymosomes was unable to displace already transferred biotinylated proteins. These results established that epididymosomes from caput and cauda epididymidis have different protein composition and interact differently with maturing spermatozoa.     

Distribution of carnitine and acylcarnitine in the hamster epididymis and in epididymal spermatozoa during maturation

The highest levels of carnitine and acylcarnitine were found in the cauda epididymidis, and spermatozoa from the cauda contained greater amounts of total carnitine (free carnitine plus acylcarnitine) than those removed from the corpus or caput epididymidis. Spermatozoa from the distal cauda contained significantly greater amounts of both free and total carnitine than those removed from the proximal cauda epididymidis. The acylcarnitine:carnitine ratio was 1.7 and 0.37 in caput and cauda spermatozoa, respectively and 1.7 and 1.3 in caput and cauda fluid, respectively. It is suggested that the accumulation of carnitine is involved in sperm maturation and that acylcarnitine serves as an energy substrate for epididymal spermatozoa.     

The histochemical localization of prostaglandin synthetase activity in reproductive tract of the male rat.

PG synthetase activity was assessed histochemically in the reproductive tract of male rats. Moderate activity was observed in tails of spermatozoa within the corpus and cauda epididymidis but there was no activity in the caput epididymidis or the seminiferous tubules. The sperm tail activity was maximal for cells within the vas deferens. PG synthetase activity was also observed in individual adipose cells adhering to the testicular capsule, epididymis and vas deferens, and in isolated interstitial cells of the testis and the caput, corpus and cauda epididymidis. Specific cells in the capsules of the testes, epididymis and vas deferens also produced PGs. The activity observed in the interstitial cells of the testis and the caput epididymidis was less than that for the other tissues in terms of the proportion of possible cells. The demonstration of PG synthetase activity paralleled to known loss of arachidonic acid from the phospholipids of the spermatozoa as they pass through the male tract. Endogenous substrate was not limiting in the assay system, even in the testis and caput epididymidis where PG synthesis was not normally observed, indicating that a PG synthesis inhibitor may be present in these two tissues. PG synthetase activity within teased seminiferous tubules was markedly increased by physical trauma. Indomethacin diminished but did not eliminate synthesis.     

beta-N-acetylglucosaminidase in the reproductive organs and seminal plasma of the bull

The highest specific activity of beta-N-acetylglucosaminidase (beta-NAG) was found in the different parts of the epididymis, where the activity seemed to be partly in secretory and partly in non-secretory, tissue-bound form. Epididymal spermatozoa also contained moderate beta-NAG activity. The beta-NAG was separated by chromatofocussing and anion exchange chromatography with HPLC into multiple forms with distinct pI values (8.0-4.0). The cauda epididymidis, ampulla and the seminal vesicles formed the major secretory sources of the high beta-NAG activity in bull seminal plasma. The major secretory forms of beta-NAG in caput and cauda epididymidis showed distinct elution profiles. In the fractionation with gel filtration on Sepharose 6B, the beta-NAG activities derived from bull testis and caput epididymidis had smaller molecular weights than did the secretory enzymes in seminal plasma, seminal vesicle secretion and cauda epididymidis. Maximum activity of all beta-NAG isoenzymes was observed at pH 5.0. They were almost totally inactivated at 60 degrees C and about 75-80% of the activity was lost at 55 degrees C. All the isoenzymes were strongly inhibited by thiol reagents but not with other metal ions and chelating agents. Histochemical studies showed a strong granular (lysosomal) reaction for beta-NAG in basal cells and basal parts of the principal cells in all but the initial segment of the epididymis. An apical (secretory) reaction was prominent in the distal caput and corpus as well as in distal cauda. After the distal caput the luminal sperm mass became increasingly mixed with a beta-NAG-positive material. The epithelial cells of the ampulla and seminal vesicle displayed a moderate apical (secretory) reaction.     

Immunocytochemical localization of alpha-lactalbumin in the male reproductive tract

The immunocytochemical localization of the milk protein alpha-lactalbumin in the male reproductive tract is described. Using a primary antiserum raised against highly purified rat milk alpha-lactalbumin, specific staining was consistently shown in the supranuclear Golgi region of the principal cells of the proximal caput epididymidis but only occasionally in epithelial cells from other regions of the duct. Staining was also found in the epididymal lumen and associated with spermatozoa. This luminal staining persisted throughout the distal caput, corpus and cauda epididymidis. Staining was rarely associated with spermatozoa in the efferent ducts and initial segment. Alpha-lactalbumin immunoreactivity was also detected in the seminiferous epithelium. Staining was confined to the Golgi-acrosome region of spermatids. These results indicate that an alpha-lactalbumin-like molecule, or molecules, is present in the male reproductive tract and that it is localized specifically in principal cells from the proximal caput epididymidis and germ cells from the seminiferous epithelium.     

Ultrastructural localization of PGP 9.5 and ubiquitin immunoreactivities in rat ductus epididymidis epithelium

Summary The distribution of protein gene product 9.5 (PGP) and ubiquitin in the spermatozoa and epithelial cells in the different regions of the rat duetus epididymidis (proximal caput, distal caput, corpus and cauda) was studied by Western blotting analyses and electron microscopical immunogold labelling. Western blotting analyses showed that the PGP immunoreactive band was very intense in the caput and cauda epididymidis and almost irrelevant in the corpus, while the ubiquitin immunoreactive band was intense in the distal caput and cauda. No ubiquitin immunoreactive band was observed in the proximal caput and only a very weak band was seen in the corpus. The results of electron microscopical immunogold labelling varied from one epididymal region to another. The proximal caput epididymidis presented immunoreaction to PGP in the rough endoplasmic reticulum, cytosol, mitochondria and microvilli of most principal cells, and in the cytosol, rough endoplasmic reticulum and mitochondria of most basal cells. No ubiquitin immunoreaction was observed in this epididymal region. In the distal caput epididymidis, PGP immunoreactivity was detected in some principal and basal cells in the same intracellular locations as described in the proximal caput. In this region, ubiquitin immunoreactivity appears in the apical cytosol and mitochondria of principal cells. The corpus epididymidis showed no immunoreaction to PGP or ubiquitin. In the cauda epididymidis, immunostaining to PGP was observed in most clear cells and in isolated principal cells. The intracellular location of PGP in both cell types was the cytosol, mitochondria and microvilli. Ubiquitin immunoreactivity was detected in the perinuclear cytosol and mitochondria — but not in the digestive vacuoles — of some clear cells. Scanty ubiquitin immunolabelling was also found in the microvilli, cytosol and mitochondria of some principal cells. The head of the spermatozoa present in the ductal lumen in all epididymal regions immunoreacted intensely to PGP. Ubiquitin was detected in the intermediate piece and residual cytoplasm of intraluminal spermatozoa present in the corpus and cauda epididymidis. These findings suggest that a non-ubiquitinated PGP irnrnunoreactive protein is secreted by the principal cells in caput epididymidis and binds the spermatozoon heads. It is possible that the clear cells of the cauda epididymidis secrete the ubiquitin that binds to spermatozoon tail.     

Effects of caput ligation on rat sperm and epididymis: protein thiols and fertilizing ability.

Mammalian spermatozoa mature while passing through the epididymis. Maturation is accompanied by thiol oxidation to disulfides. In rats, sperm become motile and fertile in the cauda. We have previously demonstrated that rat caput sperm contain mostly thiols and that upon passage from the corpus to the cauda epididymidis, sperm protein thiols are oxidized. The present work was undertaken to study the role of the regions of the epididymis in sperm maturation as reflected in the thiol status, fertility, and motility of the spermatozoa. The distal caput epididymidis of mature albino rats was ligated on one side. After 5 days, sperm were isolated from the ligated caput and from caput and cauda of the control side. Thiol groups in sperm, epididymal luminal fluid (EF), and epididymal tissue were labeled using the fluorescent thiol-labeling agent monobromobimane. After ligation, changes were observed in a) sperm proteins, sperm nuclear proteins, and epididymal fluid by electrophoresis; b) epididymal tissues by histochemistry; c) progressive motility by phase microscopy; and d) fertilizing ability after insemination into uteri of immature females. We found that after ligation, caput sperm thiols, especially protamine thiols, are oxidized, rendering them similar to mature sperm isolated from the cauda epididymidis. Spermatozoa from ligated caput epididymidis gain progressive motility and partial fertilizing ability. Morphology of epithelial cells of ligated caput is similar to that of cauda cells. However, other changes in caput EF and epithelium induced by ligation render the ligated caput epididymidis different from either control caput or cauda. Hence, sperm thiol oxidation, along with the development of fertilizing ability, can occur in sperm without necessity for sperm transit through the corpus and cauda epididymidis.     

Influence of epididymal maturation on the capacity of hamster and rabbit spermatozoa for complement activation

Hamster and rabbit spermatozoa released from the epididymis were tested for the ability to activate complement via the alternative pathway. While hamster spermatozoa were more active, the spermatozoa of both species reduced complement activity in homologous and also human serum previously adsorbed to remove sperm antibodies, and they bound C3 in the presence of EGTA + Mg2+. Hamster spermatozoa from the caput epididymidis were more anticomplementary and bound more C3 than did cauda spermatozoa and, though less marked, a similar difference was evident between caput and cauda spermatozoa from the rabbit epididymis.     

Effect of diabetes mellitus on epididymal enzymes of adult rats.

Diabetes mellitus caused significant reduction in serum testosterone and accessory sex glands weight. The sperm content of epididymal regions also decreased. Among the epididymal regions, the cauda epididymidal tissue alone showed significant reduction in Na(+)-K+ ATPase activity. However, Mg2+ ATPase activity was lowered in caput epididymidis only. Specific activity of Ca2+ ATPase significantly decreased in caput and cauda epididymides. All three ATPases decreased significantly in caput epididymidal spermatozoa leaving cauda epididymidal spermatozoa unaffected. Specific activity of alkaline phosphatase was suppressed in caput epididymidis and in the spermatozoa collected from caput and cauda epididymides, while the acid phosphatase was unaffected. In general, the results are suggestive of definite influence of diabetes on epididymal phosphatases which is region specific. Diabetes induced decrease in phosphatases may have an impact on secretory and absorptive functions of epididymis and thus on sperm maturation.     

The lipid content of epididymal spermatozoa of Rattus norvegicus.

1. Seven major lipids of rat spermatozoa from the caput, corpus and cauda epididymidis were separated and quantitated by TLC. 2. Spermatozoa from the caput epididymidis had a significantly greater (P less than 0.05) content of phospholipid, cholesterol, cholesterol ester and free fatty acid than those from the cauda epididymidis. 3. Spermatozoa from the corpus epididymidis had a significantly greater (P less than 0.05) content of monoglyceride than those from the caput epididymidis and a greater content of phospholipid, cholesterol, free fatty acids and monoglyceride than those from the cauda epididymidis.     

Phospholipase and lysophospholipase activities of goat spermatozoa in transit from the caput to the cauda epididymidis

Phospholipase and lysophospholipase activities were assayed in goat epididymal spermatozoa. Lysophospholipase was 10 times more active than phospholipase, and both enzymes decreased in activity substantially in the transit of spermatozoa from the caput to the cauda epididymidis. A comparative study revealed that phosphatidyl-ethanolamine, -choline and -inositol and phosphatidic acid were hydrolysed by goat sperm phospholipase. Hydrolysis of phosphatidylethanolamine/phosphatidylcholine revealed the end products to be glycerophosphoethanolamine/choline but neither diglycerides nor lysophosphatidylethanolamine/lysophosphatidylcholine were detected.     

A determinant of Mr 34,000 expressed by hamster epididymal epithelium binds specifically to spermatozoa in co-culture

A murine monoclonal antibody raised against hamster cauda epididymal spermatozoa was shown to recognize an Mr 34,000 component of epididymal epithelium. Antigen was localized by immunocytochemistry on the surface and in the apical cytoplasm of principal cells in the proximal corpus epididymidis but not in the caput or initial segment regions. Spermatozoa from the corpus epididymidis expressed antigen on their post-acrosomal plasma membrane and annulus. Epididymal principal cells from the proximal corpus region when cultured in vitro bound antibody on their apical surface for at least 5 days. Spermatozoa from the caput epididymidis co-cultured with epithelium expressed antigen after incubation for 8 and 24 h. These results suggest that a surface change to epididymal spermatozoa during maturation in vivo may also be elicited during in-vitro culture.     

Effect of glutathione depletion on antioxidant enzymes in the epididymis, seminal vesicles, and liver and on spermatozoa motility in the aging brown Norway rat

Reactive oxygen species (ROS) play a role in male infertility, where excessive amounts impair spermatozoal motility. Epididymal antioxidant enzymes protect spermatozoa from oxidative damage in the epididymal lumen. Antioxidant secretions from the seminal vesicle protect spermatozoa after ejaculation. As it is known that with age there is increased generation of ROS, the goals of this study were to determine how aging affects the response of antioxidant enzymes in the epididymis, seminal vesicles, and liver to l-buthionine-S,R-sulfoximine (BSO) mediated glutathione (GSH) depletion, and to examine the impact of GSH depletion on motility parameters of spermatozoa from the cauda epididymidis in young (4-mo-old) and old (21-mo-old) rats. Levels of GSH and glutathione disulfide (GSSG), as well as activities of glutathione peroxidase, glutathione reductase, catalase, and superoxide dismutase, were measured in the caput, corpus and cauda epididymidis, seminal vesicles, and liver. Spermatozoal motility was assessed by computer-assisted sperm analysis. Significant age-related changes in antioxidant enzyme activities were found in the liver and cauda epididymidis. Glutathione depletion clearly affected tissues in both young and old. The compounding effect of age was most evident in the cauda epididymidis, seminal vesicles, and liver, where antioxidant enzyme activities changed significantly. Additionally, spermatozoa motility was adversely affected after BSO treatment in both age groups, but significantly more so in older animals. In summary, the male reproductive tissues and liver undergo age-related changes in antioxidant enzyme activities and in their response to GSH depletion.     

Role of epithelial clear cells of the rat epididymis in the disposal of the contents of cytoplasmic droplets detached from spermatozoa

Upon release from the seminiferous epithelium, spermatoza show a small droplet of cytoplasm attached to the neck region. During transit of spermatozoa in the caput epididymidis, this cytoplasmic droplet migrates along the middle piece of the flagellum. In the corpus epididymidis, the droplet shows a lateral displacement, while in the cauda epididymidis it detaches from the spermatozoon. In the electron microscope, cytoplasmic droplets attached to spermatozoa were seen to contain numerous, short, straight or C-shaped, flattened membranous elements referred to as lamellae, small vesicles, and small particles (35-nm diameter) with a diffuse wall showing no apparent unit membrane. The lamellae were stacked closely on one another or arranged in a loose array. Structurally as well as cytochemically, with different cytochemical markers, the lamellae and vesicular elements failed to show any evidence of being components of the Golgi apparatus or elements of the endoplasmic reticulum. The lamellae, vesicular elements, and 35-nm particles were also seen free in the lumen of the corpus epididymidis but were especially prominent in the cauda epididymidis at a time when droplets were being released from spermatozoa. The lumen of the epididymis, as spermatozoa passed from the caput to the cauda epididymidis, was also noted to acquire progressively a flocculent background material. The epididymal epithelium is composed predominantly of principal and clear cells. The endocytic activity of clear cells was examined in rats at different time intervals after a single injection of cationic ferritin into the lumen of the cauda epididymidis. At 2 min the tracer was bound to the microvilli of these cells and was also observed within large coated and uncoated pits, subsurface coated vesicles, and numerous subsurface small uncoated vesicular membranous elements (150-200-nm diameter). At 5 min, in addition to the above structures, the tracer was present in endosomes, while at 15 and 30 min, pale and dense multivesicular bodies appeared labeled, respectively. At 1 and 2 hr, but more so at 6 hr large dense membrane-bound bodies identified cytochemically as secondary lysosomes became labeled. All of the above endocytic structures were also seen to contain the 35-nm particles, flattened or vesicular membranous profiles, and a fine flocculent background material reminiscent of those seen free in the lumen or found in cytoplasmic droplets attached to spermatozoa. (ABSTRACT TRUNCATED AT 400 WORDS)     

Fine structure distribution of non-specific acid phosphatase in the head region of mouse spermatozoa from various regions of the male reproductive tract.

The fine structure distribution of non-specific acid phosphatase was determined in the head region of mouse spermatozoa from the testes, the caput, corpus and cauda epididymidis and the ductus deferens. Enzymatic localization was achieved by the Gomori technique. The postacrosomal dense lamina, the nuclear side of the inner acrosomal membrane and the space between the plasmalemma and the outer acrosomal membrane showed reaction product in spermatozoa from the testis and caput epididymidis. Spermatozoa from the cauda epididymidis exhibited reaction product only between the plasmalemma and the outer acrosomal membrane. Spermatozoa from the corpus epididymidis and from the ductus deferens showed no reaction product in the head region. The changes observed in the distribution of acid phosphatase in the sperm head during epididymal transport may reflect maturational events.     

Beta-galactosidase in the seminal plasma and reproductive organs of the bull

The distribution of beta-galactosidase activity was studied in different reproductive organs, seminal plasma and spermatozoa of the bull. The highest specific activity of beta-galactosidase was found in testis and in different parts of the epididymis, where the activity seemed to be partly in secretory (cauda secretion) and partly in non-secretory, bound form (caput to cauda epididymidis). Gel filtration on Sepharose 6B at pH 7.0 revealed two beta-galactosidase forms (GF-1, Mr approximately 500,000-600,000 and GF-2, Mr approximately 190,000-220,000) in reproductive organs and seminal plasma. The pH-optimum of both beta-galactosidase forms was about 3.75-4.75. Hg2+ and p-chloromercuribenzoate inhibited strongly these activities. Further, form GF-2 seemed to be slightly more sensitive to the thermal inactivation at 50-70 degrees C than form GF-1. In chromatofocusing beta-galactosidase activities in bull seminal plasma coeluted with those of the cauda epididymidis (pI-values 7.5-6.4). On the contrary, prostate, Cowper's gland, testis, ampulla and seminal vesicles had enzyme activities eluting at lower pI-values (6.3-4.2). Thus, the seminal plasma activity is mainly an indicator for the function of the epididymal cauda.     

Structural features of the epididymis in a dasyurid marsupial (Antechinus stuartii)

Summary The ductus epididymidis of the marsupial mouse Antechinus stuartii was divided into caput, corpus, and caudal regions using several constant morphological landmarks. Tubule diameter and epithelial height increased gradually from caput to cauda. In contrast, the surface area of the lumen of the ductus epididymidis increased to a maximum in the distal caput region, but decreased markedly in the distal cauda in association with characteristic changes in lumen shape (from circular to slit-shaped) and epithelial height. Epithelial cells of the ductus epididymidis were generally similar in structure to those described in other mammalian species. Principal and basal cells were common throughout the epithelium. Clear and mitochondria-rich cells were also identified, but occurred less frequently. Regional variations in cell ultrastructure were observed only in principal cells. Numerous vesicular inclusions occurred in the apical cytoplasm of cells in caput segments, membrane-bounded, electron-dense bodies were common in distal corpus regions, and a brush border of microvilli characterized the luminal surface of principal cells in caudal segments. Sperm index increased in the proximal caput, declined to basal levels in the distal caput and proximal corpus, and then increased to a maximum in segment 9 of the distal corpus and remained at about this level throughout the cauda epididymidis. Nuclear rotation, loss of cytoplasmic droplets, and other sperm maturational changes were observed along the epididymis. Discarded cytoplasmic droplets collected in large masses interspersed between aggregates of spermatozoa throughout the distal regions of the duct. There was no evidence of phagocytosis by principal cells of cytoplasmic droplets. The epididymis of A. stuartii differs from that of other mammals. The unusual caudal region, which has little storage capacity for sperm, is an unusual adaptation in a species in which the male is known to be polygamous.     

Dicarbonyl L-Xylulose Reductase (DCXR), a “Moonlighting Protein” in the Bovine Epididymis

During maturation and the acquisition of their fertilization potential, male germ cells are subjected to various sequential modifications that occur in the epididymis. Protein addition, reorganization or withdrawal, comprise some of these modifications. Dicarbonyl L-xylulose reductase (DCXR), a multifunctional protein involved in various enzymatic and protein interaction processes in different physiological systems, is one of the proteins added to spermatozoa in the epididymis. DCXR is a well-conserved protein with multiple characteristics including enzymatic activities and mediation of cell-cell interaction. In this study, we characterized the DCXR gene and protein expression in the bovine epididymis. Dicarbonyl L-xylulose reductase mRNA is differentially expressed in the caput, corpus, and cauda epididymide epithelial cells with a higher level observed in the cauda region. Tissue protein expression follows the same pattern as the corresponding mRNA expression with a cytoplasmic and apical distribution in the corpus and cauda epithelial cells, respectively. The protein can also be found with a nuclear localization in cauda epididymidis epithelial cells. Dicarbonyl L-xylulose reductase is secreted in the epididymis luminal compartment in the soluble fraction and is associated with microvesicular elements named epididymosomes. In spermatozoa, the DCXR protein was found in the cytoplasmic and membranous fractions. Expression of the DCXR protein is higher on caput spermatozoa but finally shows a weak detection in semen. These data describe DCXR in the bovine epididymis and reveal that its behavior differs from that found in humans. It seems that, in this model, the DCXR protein might have a questionable involvement in the fertilization process.     

Different expression of lipocalin-type prostaglandin D synthase in rat epididymidis

This study was designed to explore the different expression of L-PGDS (lipocalin-type prostaglandin D synthase) in rat epididymidis and to gain further insight into the potential function of L-PGDS in male reproduction. The expression of L-PGDS in rat epididymidis was assessed using real-time quantitative PCR and immunoblotting. The distribution of L-PGDS in rat epididymidis was explored by immunohistochemical methods. The result of immunohistochemistry displayed that L-PGDS was mainly distributed in epididymidis and localized within the cytoplasm and the cilia of the epithelial cells. Real-time quantitative PCR and immunoblotting showed that L-PGDS was strikingly expressed in the caput epididymidis, while a moderate to weak expression was observed in the corpus and cauda epididymidis, the level of mRNA was 0.52+/-0.02 in the caput, 0.48+/-0.03 in the corpus and 0.32+/-0.01 in the cauda epididymidis, the level of protein expression in caput, corpus and the cauda groups was 1, 0.89+/-0.03 and 0.62+/-0.01, which suggested that L-PGDS may play certain kind of role during the process of the spermatozoa maturation.