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1.
A simple trypan blue-neutral red-Giemsa staining procedure for simultaneous evaluation of acrosome, sperm head, and tail membrane integrity and morphology has been used to evaluate equine spermatozoa. Some special characteristics and problems have arisen in evaluating stallion semen. One problem was the differentiation of intact vs. damaged sperm tails primarily in frozen and thawed samples. After freezing and thawing, a high percentage of spermatozoa with an unstained head and stained tail were observed. These cells are considered immotile. Therefore, unambiguous differentiation of intact vs. damaged sperm tail membrane is very important for evaluating semen quality. The aim of our study was to develop a method especially for stallion sperm to distinguish more accurately the different cell types. We compared Chicago sky blue 6B (CSB) to trypan blue (TB) for viability staining. CSB/Giemsa staining showed good repeatability and agreement with TB/Giemsa measurements. For densitometry analysis, individual digital images were taken from smears stained by CSB/Giemsa and by TB/Giemsa. A red-green-blue (RGB) histogram for each area of spermatozoa was drawn. Differences of means of RGB values of live vs. dead tails and separate live vs. dead heads from each photo were used to compare the two staining procedures. CSB produced similar live/dead sperm head differentiation and better tail differentiation. TB can be replaced by CSB and this results in more reliable evaluation. After staining with 0.16% CSB and 4 min fixation, 2–4 h Giemsa staining at 25–40° C is recommended for stallion semen.  相似文献   

2.
A simple trypan blue-neutral red-Giemsa staining procedure for simultaneous evaluation of acrosome, sperm head, and tail membrane integrity and morphology has been used to evaluate equine spermatozoa. Some special characteristics and problems have arisen in evaluating stallion semen. One problem was the differentiation of intact vs. damaged sperm tails primarily in frozen and thawed samples. After freezing and thawing, a high percentage of spermatozoa with an unstained head and stained tail were observed. These cells are considered immotile. Therefore, unambiguous differentiation of intact vs. damaged sperm tail membrane is very important for evaluating semen quality. The aim of our study was to develop a method especially for stallion sperm to distinguish more accurately the different cell types. We compared Chicago sky blue 6B (CSB) to trypan blue (TB) for viability staining. CSB/Giemsa staining showed good repeatability and agreement with TB/Giemsa measurements. For densitometry analysis, individual digital images were taken from smears stained by CSB/Giemsa and by TB/Giemsa. A red-green-blue (RGB) histogram for each area of spermatozoa was drawn. Differences of means of RGB values of live vs. dead tails and separate live vs. dead heads from each photo were used to compare the two staining procedures. CSB produced similar live/dead sperm head differentiation and better tail differentiation. TB can be replaced by CSB and this results in more reliable evaluation. After staining with 0.16% CSB and 4 min fixation, 2-4 h Giemsa staining at 25-40 degrees C is recommended for stallion semen.  相似文献   

3.
A study of the morphological characteristics of stallion spermatozoa was conducted at the semen laboratory of the Department of Animal Production during four breeding seasons. A total of 590 ejaculates collected from 216 stallions aged from 2 to 26 years and including 13 breeds or colour types was examined. Overall means for the spermatozoal characteristics of these stallions and the classes of head and tail abnormalities are presented and compared with results of other works. Scanning electron micrographs are included to illustrate recognised abnormalities.  相似文献   

4.
The presence and distribution of cholesterol in mature and immature epididymal spermatozoa was analyzed using filipin as a cytochemical tool in freeze-fracture replicas and thin section preparations. The polyenic-antibiotic filipin formed complexes with 3, beta -OH sterols, producing characteristic protrusions, or pits, that were heterogeneously distributed in the plasma membrane of stallion spermatozoa, revealing a specific organization in a functionally specialized area of the gamete. The acrosomal region of the sperm head presented a significantly higher density of filipin sterol complexes than the postacrosomal region, which was usually free of these complexes. The plasma membrane of the flagellum also showed filipin sterol complexes randomly distributed in freeze-fracture replicas. The strong filipin labeling observed in the membrane of spermatozoa obtained from the caput region of the epididymis decreased significantly during epididymal passage. The significance of these changes is not completely understood, but they might contribute to establishing the molecular organization necessary for sperm transit and storage in the epididymis as well as to development of motile spermatozoa that are able to fertilize the oocyte and induce normal embryonic development.  相似文献   

5.
The abundance of data pertaining to the metabolism of lipids in relation to mammalian fertilization has warranted an effort to assemble a molecular membrane model for the comprehensive visualization of the biochemical events involved in sperm capacitation and the acrosome reaction. Derived both from earlier models as well as from current concepts, our membrane model depicts a lipid bilayer assembly of space-filling molecular models of sterols and phospholipids in dynamic equilibrium with peripheral and integral membrane proteins. A novel feature is the possibility of visualizing individual lipid molecules such as phosphatidylcholine, phosphatidylethanolamine, lysophospholipids, fatty acids, and free or esterified cholesterol. The model illustrates enzymatic reactions which are believed to regulate the permeability and integrity of the plasma membrane overlying the acrosome during interactions between the male gamete and capacitation factors present in fluids of the female genital tract. The use of radioactive lipids as molecular probes for monitoring the metabolism of cholesterol and phosphatidylcholine revealed the presence of (1) steroid sulfatase in hamster cumulus cells, (2) lecithin: cholesterol acyltransferase in human follicular fluid, (3) phospholipase A2, and (4) lysophospholipase in human spermatozoa. These enzymatic reactions can be integrated into a pathway that provides a link between the concepts of lysophospholipid accumulation in the sperm membranes and alteration of the cholesterol/phospholipid ratio as factors involved in the preparation of the membranes for the acrosome reaction. Capacitation is viewed as a reversible phenomenon which, upon completion, results in a decrease in negative surface charge, an efflux of membrane cholesterol, and an influx of calcium between the plasma and outer acrosomal membranes. Triggered by the entry of calcium, the acrosome reaction involves phospholipase A2 activation followed by a transient accumulation of unsaturated fatty acids and lysophospholipids implicated in membrane fusion which occurs during the formation of membrane vesicles in spermatozoa undergoing the acrosome reaction.  相似文献   

6.
Human ejaculated spermatozoa were washed through a Percoll gradient, preincubated for 10 hr in a defined medium containing serum albumin, and then induced to undergo rapid acrosome reactions by addition of human follicular fluid or a Sephadex G-75 column fraction of the fluid. Induction by follicular fluid did not occur when the spermatozoa were preincubated for only 0 or 5 hr. The reactions were detected by indirect immunofluorescence using a monoclonal antibody directed against the human sperm acrosomal region. The percentage of acrosomal loss counted by transmission electron microscopy agreed with that counted by immunofluorescence. The apparent molecular weight of the Sephadex G-75 fraction containing the peak of acrosome reaction-inducing activity was 45,000 ± 4,200 (SD). The occurrence of physiological acrosome reactions was supported by: assessing motility (no significant loss of motility occurred during the treatment period when sperm were preincubated with bovine serum albumin), transmission electron microscopy (the ultrastructural criteria for the acrosome reaction were met), and zona-free hamster oocyte binding and penetration (spermatozoa pretreated with the active fraction of follicular fluid, then washed and incubated with oocytes, showed significantly greater binding to and penetration of oocytes). The stimulation of the acrosome reaction by follicular fluid is apparently not due to blood serum contamination; treatment of preincubated spermatozoa with sera from the follicular fluid donors had no effect on the spermatozoa. The nature of the active component(s) in that fraction is currently being investigated.  相似文献   

7.
The majority of the spermatozoa precapacitated in Ca2+-free medium underwent the acrosome raction rapidly when they were transferred to Ca2+-containing medium. The presence of Na+ and Ca2+ in the medium was essential for the acrosome reaction. The vast majority of spermatozoa failed to undergo the reaction in Ca2+ medium lacking monovalent ions, although they remained motile. At the concentration of 140 mM, Na+, K+, Rb+, and Cs+ all supported the reaction at the maximum level, but at 50 mM the latter three ions were not as effective as Na+. Li+ was least effective in supporting the reaction. Virtually no acrosome reactions took place when precapacitated spermatozoa were first exposed to Na+ medium (no Ca2+) and then to Ca2+ medium (no Na+). On the other hand, a considerably higher proportion of spermatozoa acrosome reacted when they were exposed to these media in the reverse order. The most efficient acrosome reactions took place when the medium contained both a monovalent ion (Na+) and Ca2+ simultaneously. Possible mechanisms by which monovalent and divalent cations participate in the acrosome reaction are discussed.  相似文献   

8.
The effect of the calmodulin antagonist W-7 on the capacitation and the acrosome reaction of guinea pig spermatozoa was examined. The characteristic features of the acrosome reaction induced by W-7 were the dependence on the composition and pH of the medium and on the presence of sodium bicarbonate. The most effective concentration of W-7 for inducing the acrosome reaction was approximately 5 μM, which is far less than the Kd for calmodulin. Moreover, W-7 enhanced the ability of spermatozoa to acquire capacitation in a Ca2+-free medium. The spermatozoa induced to undergo the acrosome reaction by W-7 were capable of penetrating the zona-free hamster eggs. W-5, which has a lower affinity for calmodulin than W-7, also induced the acrosome reaction in the same manner as W-7. These results suggest that the naphthalenesulfonamide derivatives W-7 and W-5 can induce the acrosome reaction in guinea pig spermatozoa via capacitation in a pH-dependent, Ca2+-calmodulin-independent manner.  相似文献   

9.
The effects of lipids on the survival, acrosome reaction, and fertilizing capacity of guinea pig spermatozoa were studied by incubating the spermatozoa in media containing various concentrations of the lipids. Lipids tested were: phosphatidyl-choline (PC), -ethanolamine (PE), -inositol (PI), -serine (PS), sphingomyelin (S), cholesterol (C), lysophosphatidyl-choline (LC), -ethanolamine (LE), -inositol (LI), -serine (LS), and glyceryl monooleate (M). When spermatozoa were incubated in a regular medium (containing 2 mM Ca2+) with M, the majority underwent the acrosome reaction within 1 hour. None of the other lipids were as effective as M, and some were totally ineffective under the same conditions. However, when spermatozoa were preincubated in Ca2+-free medium containing LC, LE, or LI, they gained the ability to undergo the acrosome reaction. One hour of preincubation in Ca2+-free medium with LC, LE, or LI was enough to render the vast majority of spermatozoa capable of undergoing the acrosome reaction in response to Ca2+. The optimum concentrations for LC, LE, and LI were approximately 85 μg/ml, 210 μg/ml, and 140 μg/ml, respectively. Spermatozoa that had undergone the acrosome reaction by pretreatment with LC, LE, or LI remained actively motile and were capable of fertilizing eggs. LS was totally ineffective in rendering the spermatozoa capable of undergoing the acrosome reaction, and in fact it inhibited the acrosome reaction by itself and also inhibited the LC-, LE-, or LI-mediated acrosome reaction. LS did not prevent acrosome-reacted spermatozoa from penetrating the zona pellucida, but did prevent sperm-egg fusion. Based on these findings, it is suggested that lysophospholipids are intricately involved in the sperm acrosome reaction and perhaps in sperm-egg fusion.  相似文献   

10.
A simple dual stain procedure (DS) for simultaneously determining sperm viability and acrosomal status is described. The DS includes the use of the vital stain trypan blue to detect live and dead spermatozoa and Giemsa to detect the presence or absence of an acrosome. For staining, spermatozoa are washed, incubated with trypan blue, washed, dried onto slides, and subjected to Giemsa. Dead spermatozoa stain blue in the postacrosomal region while live spermatozoa remain unstained. The acrosome stains light purple–dark pink while acrosome-free sperm remain unstained. This staining pattern enables differentiation of spermatozoa which have undergone a true acrosome reaction (TAR) from those which have undergone a false acrosome reaction (FAR). Incubation of bull, boar, ram, and stallion spermatozoa for 60 minutes at 37°C in the presence of calcium ionophore A23187 increased the proportion of spermatozoa undergoing a TAR in all species except the stallion. Incubation of bull spermatozoa for up to 24 hours at 37°C resulted in a decrease over time in the percentage of live acrosome-intact spermatozoa and a simultaneous increase in the percentage of spermatozoa categorized as having undergone a TAR and FAR. The DS could be a useful technique in evaluating sperm viability and acrosomal status in fertilization and clinical studies.  相似文献   

11.
The involvement of a kallikrein−kinin system in the motility of mammalian spermatozoa has been suggested by several investigators. We found that incorporation of kallikrein (0.1–1.0) unit/ml) in the sperm incubation medium did not enhance the motility of hamster spermatozoa that were already active. However, this enzyme significantly increased the incidence of the acrosome reaction. Trypsin (1.8–18 units/ml) and chymotrypsin (0.34–3.4 units/ml) also increased the incidence of the acrosome reaction, and accelerated its onset. Kinins (bradykinin and kallidin) added to the medium in a wide concentration range (1 ng/ml to 1 mg/ml) had no marked effects on either the motility or the acrosome reaction. A kallikrein−kinin system is apparently not of primary importance at least for the acrosome reaction. The enhancement of the acrosome reaction by exogenous proteinases may be due in part to accelerated removal or alteration of the sperm surface coat (glycoprotein) by the enzyme peior to the acrosome reaction. Exogenous proteinases may also act synergistically with endogenous (acrosomal) proteinases (and other enzymes) in altering membrane proteins and dispersing the acrosome matrix during the course of teh acrosome reaction.  相似文献   

12.
When guinea pig spermatozoa are preincubated for 1 hr in Ca2+?free medium containing a low concentration of lysolecithin (LC, 85 μg/ml) and then exposed to 2 mM Ca2+ by diluting the preincubation medium with an equal volume of LC?free, 4 mM Ca2+?containing medium, the majority of the spermatozoa undergo acrosome reaction promptly. On the other hand, when the preincubated spermatozoa are exposed to 2 mM Ca2+ without reducing the original concentration of LC in the medium, none of them undergo acrosome reaction. These spermatoza can acrosome?react if they are transferred to an LC?free medium. These results and those of some other experiments suggest that in the presistent presence of a high concentration of LC in the medium, exogenous Ca2+ essential for the acrosome reaction either does not penetrate the sperm plasma membrane or, if it does, it cannot alter the membrane for the acrosome reaction, at least under the experimental conditions employed. Freeze?fracture examination of the sperm plasma membrane has revealed that small areas or patches free of intramembranous paarticles (IMPs) appear in the membrance during sperm preincubation, and these IMP?free areas expand drastically in response to Ca2+ when the LC conccentration in the medium is reduced at the time Ca2+ is added to the medium. In contrast, IMP?free areas remain unchanged even after exposure of spermatozoa to Ca2+ if the concentration of LC remains at its original level of 85 μg/ml.  相似文献   

13.
The effects of seven surfactants on spermatozoa of the sea urchin, Hemicentrotus pulcherrimus, were studied. All these surfactants induced the acrosome reaction and inhibited the fertilizing capacity of spermatozoa. There was a statistically significant correlation between the concentrations that induce the acrosome reaction and inhibit fertilization. The critical micelle concentrations (CMC) of surfactants in sea water were almost even and these values, which are inherent physical properties of surfactants, did not provide a direct measure of their inhibitory effect of fertilization. Among seven surfactants, p-menthanyl-phenol polyoxyethylene (8.8) ether (TS-88) with a characteristic hydrophobes was the most potent both in the induction of acrosome reaction and in the inhibition of fertilization. Various ethylene oxide adducts to p-menthanyl-phenol were also tested for the purpose of comparison. It is suggested that the effects of surfactants on sea urchin spermatozoa at low concentrations reflect their activity associated with the hydrophobic group inherent in each surfactant.  相似文献   

14.
A system has been developed for inducing a calcium-dependent acrosome reaction in ram spermatozoa in vitro using the calcium ionophore A23187. The resultant reaction is accompanied by release of the acrosomal enzymes hyaluronidase and acrosin, but there is no release of the cytoplasmic enzyme glucose 6-phosphate isomerase. In any given cell, the visible acrosome reaction apparently takes place rapidly, but there is a variable delay before the reaction occurs. Under optimum conditions, about 90% of treated spermatozoa show an acrosome reaction within one hour. Preincubation of the spermatozoa with the proteinase inhibitors p-amino-benzamidine or p-nitrophenylguanidinobenzoate allows two stages of the reaction to be distinguished ultrastructurally, a membrane fusion stage followed by a dispersal of the acrosomal matrix. In the presence of the inhibitors, the first stage is delayed but is completed within 1 hour, whereas the second remains largely incomplete. In the presence of calcium, ionophore concentrations which induce an acrosome reaction abolish sperm motility rapidly and completely. However, by adding serum albumin shortly after addition of ionophore, motility can be preserved while the acrosome reaction occurs as usual; the motility pattern observed under these conditions is of the “whip-lash” or “activated” type. Although the motile ionophore-treated spermatozoa were unsuccessful at penetrating normal mature sheep oocytes in vitro, they were able to penetrate zona-free oocytes, after which swelling and decondensation of the sperm head took place.  相似文献   

15.
The balancing effects of bulbourethral gland secretion (BUS) and of seminal vesicle secretion (SVS) on goat semen quality were previously demonstrated. In the present study, electron microscope observations revealed a high frequency of spermatozoa with a reacted acrosome among spermatozoa from cauda epididymis exposed to BUS in the presence of milk. This frequency was significantly reduced when SVS had been added either before or after BUS. No reacted acrosome was observed in the absence of milk. All mount spermatozoa were incubated with milk or SVS or BUS or combinations of the three materials labeled with colloidal gold. SVS attached specifically on the plasma membrane covering the anterior part of the acrosome, whereas BUS spread all over the sperm head. Milk attached on the anterior half of the sperm head only when BUS was present in the sperm environment. It is concluded that BUS plays an active role in the induction of the acrosome reaction in the presence of milk and that SVS counteracts this role.  相似文献   

16.
The effects of Ca2+ channel antagonists on the motility and acrosome reaction of guinea pig spermatozoa were examined by incubating the spermatozoa continuously in Ca2+-containing capacitating media with 10?6 M to 10?4 M antagonist. Antagonists tested were four voltage-gated Ca2+ channel antagonists (verapamil, nifedipine, nimodipine, and FR–34235) and two ligand-gated channel antagonists (NaNO2 and Na-nitroprusside). None of these antagonists could block the acrosome reaction. Instead, three antagonists (verapamil, nimodipine, and FR-34235, each at 10?4 M) accelerated the onset of the acrosome reaction with a subsequent decrease in sperm motility. Nifedipine and Na-nitroprusside at the same concentration caused a complete loss of sperm motility by 4 hr of incubation with no substantial effect on the rate of acrosome reaction. The detrimental effect of antagonists on the motility of spermatozoa appears to be due to a direct, Ca2+-independent, membrane-perturbing action of the reagents. The acrosome reaction was not inhibited when guinea pig spermatozoa were precapacitated in Ca2+-free medium (with a low concentration of lysolecithin) in the continuous presence of antagonists. An acceleration of the onset of the acrosome reaction by verapamil (10?4 M) was also demonstrated in the golden hamster. These results may be interpreted as indicating that the entry of extracellular Ca2+ into spermatozoa, which triggers the acrosome reaction of guinea pig and hamster spermatozoa, is not mediated by Ca2+ channels. This is in marked contrast with the case reported in invertebrate spermatozoa. Possible mechanisms by which some of the antagonists stimulate the acrosome reaction and affect the motility of mammalian spermatozoa are discussed.  相似文献   

17.
Viability assessment of dog spermatozoa using flow cytometry   总被引:3,自引:0,他引:3  
The percentages of living and dead spermatozoa in fresh dog semen samples were assessed by means of a dual staining technique using carboxifluorescein diacetate (CFDA) and propidium iodide (PI). Two ejaculates were obtained from dogs, each ejaculate was divided into 4 aliquots, and different proportions of freeze-killed cells were added to each aliquot. Data obtained by flow cytometry analysis of each sample were compared with those obtained by the microscopic evaluation under epifluorescence illumination and by phase-contrast microscopy evaluation of the samples stained with eosin-nigrosin. Regression analysis was used to compare the 3 methods for membrane integrity assessment of canine spermatozoa, and high correlation coefficients were found between the flow cytometry procedure and the 2 microscopy techniques. The results from this study validate the use of flow cytometry as a precise method for assessing the viability of dog spermatozoa.  相似文献   

18.
Zona-free hamster ova interacted with bull and stallion spermatozoa after treatment of ejaculated semen to capacitate the sperm cells. Sperm conditioning by prolonged incubation in BWW medium (18–26 hr) prior to insemination was effective for capacitation of bull and stallion sperm. Preincubation of bull sperm for 70 or 105 min in defined medium (DM) with NaCl content elevated to result in 350 m0sM/kg also led to penetration of hamster vitelli. More rapid sperm conditioning was possible and higher proportions of interacting vitelli followed insemination with bull or stallion sperm exposed to high ionic strength DM (380–390 m0sM/kg) for 10 min before incubation in isotonic DM prior to insemination, the treatment adopted in subsequent work. Initial efforts to assess relative fertilizing ability of freshly ejaculated semen from two fertile bulls (A and B) in A1 usage resulted in uniformly high ( > 90%) levels of sperm-vitelli interaction (for both) when the hamster ova employed resulted from superovulation with PMSG and HCG. Following use of ova from untreated hamsters sperm samples of bull A and bull B interacted with 53.8% and 84.9% (P < 0.05) of zona-free hamster ova, respectively. Conception data (60–90 day nonreturn rates) resulting from A1 with semen collected during the same interval but processed and stored in liquid nitrogen prior to use revealed an inverse relationship to proportions of vitelli interacting with fresh sperm; nonreturn rates were 69.3% and 66.3% for bull A and bull B, respectively. A similar treatment effected capacitation of frozen-stored bull semen to enable sperm-vitelli interaction. These findings encourage additional efforts to correlate testing of processed semen with fertility.  相似文献   

19.
There is controversy about whether the presence of some seminal plasma (SP) in an equine insemination dose is necessary for promoting fertility. A new technique for improving stallion sperm quality, single layer centrifugation (SLC) using a species-specific colloid, Androcoll-E, selects a sperm subpopulation that is highly motile with normal morphology, intact membranes and good chromatin integrity from the rest of the ejaculate and removes SP. The present study was designed to investigate the effect of restoring homologous SP (5% and 10%) on the progressive motility, velocity, and chromatin integrity of SLC-selected stallion spermatozoa in 44 semen samples over time. Sperm progressive motility (P < 0.01) and the proportion with class A velocity (>50 μm/sec) were increased in samples where SP was restored, whereas the proportion with class B velocity (10 to 50 μm/sec) was decreased compared with SLC samples. However, after 24 h cold storage of treated samples, progressive motility was not different for the SP-treated groups compared with SLC, whereas chromatin damage DNA fragmentation index (%DFI) was higher. In contrast, adding SP to untreated 24 h-stored SLC samples did not affect progressive motility although it did increase the proportion of spermatozoa with class A velocity. There was individual variation between stallions whether 5% or 10% SP produced a greater increase in progressive motility. In conclusion, 5% to 10% SP can be added back to SLC-selected samples if considered necessary to optimize fertility. However, it should be added immediately before insemination rather than before storage of the sperm dose, to benefit from the transient increase in sperm progressive motility and avoid increased chromatin damage.  相似文献   

20.
目的 探讨芝加哥天蓝染色法对甲真菌病患者标本检测效果.方法 收集皮肤科门诊确诊的甲真菌感染患者标本160例,同时用KOH湿片法、荧光染色法和芝加哥天蓝染色法对真菌进行镜下形态学观察,并比较真菌检出率.结果 芝加哥天蓝染色法和荧光染色法对真菌的形态结构清晰易辨.芝加哥天蓝染色法、荧光染色法和KOH湿片法的检出率分别为60...  相似文献   

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