| Clinically, 10%couples experiences infertility,and male factor is about 40%. At present ,semen parameter assay and sperm funtion detection are main methods used in evaluation of man fertility.Sperm funtion detection are,however,advanced technique,time-consuming and more expensive and not always available in routine laboratories.Therefore,conventional semen analysis ,which included PH,appearance,consistence,liquefied time,Morti lity,vitality,Concentration of WBC,still remans the cornerstone in diagnosis of man infertility. Nevertheless,some studies showed there were infertile man of 50% who had sperm morphological defection in their semen.Sperm morphology is intimately correlated with its function.Any morphological defetion will result in functional decrease,and influence male fertility.For this reason ,sperm morphology is regarded as valuable marker inreflecting semen quality.Sperm morphology ,directly correlated with fertilization in vitro,is good predictor for ferilization in vitro.So, some authors think it as the best marker in evaluation of male fertility. The percentage of morphologically normal sperm correlates significantly with insemenation, and is more useful as predictor of insemenation than sperm concentration,semen volume and sperm mortility.There are, however,many discussion about the importence of sperm morphology,and the value of sperm morphology has often been challenged by some results of esperiment in the world.In this study,the relationship between sperm morphology and conventional semen parameters was analysised,so that we can investigate if sperm morphology could reflect semen quality.Our results showed: ①The mean values for morphologically normal spermatozoa in normal fertile group was significantly higher than that in infertile group(P<0.001).Compa-red with the normal fertile group,the mean percentage of noral spermatozoa morphologically in normal fertile group significantly decreased in those groups which showed abnomal respectively in semen PH,semen volumeconcentration,motility and seminal leukocyte concen Tration (p<0.001).Meanwhile,the percentage of large head sperm,small head sperm,tapered sperm and vacuoles sperm are all significantly higher than that of fertile group(p<0.05). It is thus clear that abnormal sperm morphology is importance fator resulted in decrease in male fertility. ②In these group which respectively appearded abnormal in semen PH,semen consistence,acrosin activity,sperm viability,sperm concentration and sperm motility,the percentage of abnormal sperm morphologically significantly higher than corresponding control group(p<0.05,p<0.001).And significant relationship was foud between sperm morphology and sperm motion parameters(p<0.05,p<0.001).Obviously, the percentage of morphologically normal sperm,in some extent,could reflect semen quality. Several facors are responsible for male infertility,including chemical factor, physic factor, biological factor, drug factor and so on.These factors could result in sperm defection.The effect on sperm norphology , which arised from alcohol,smoking and steam bath,was studied.Our results exhibited the percentage of abnormal sperm morphologically in drinking group,smoking group and steam bath group was respectively higher than corresponding control group(p<0.05).Following could explain the mechanism of increased percentage of abnormal sperm morphologically due to these factors:①these factors could act on hypothalamus-pituitary-gonadal axis and weaken simulation on gonad,which could influence on spermiogenesis and secretion of sex hormone, thereby,lead to sperm defection.;②these factors could influence on Sertoli's cell and spermiogenesis;③chromosomes of germ cells could be impaired orgenerate mutation,which would lead to sperm defection; ④these factors could influence on epididymidis function and disturb sperm maturation,which would prohibit sperm from maturation; ⑤these factors can transport some substance to semen plasma through blood stream,subsequently, change microenvironment around sperm ,which could alter sperm function or structure and lastly make sperm abnormal. Sperm nuclear is the transferor of the genetic material, therefore it is powerful important in the process of spermatogenesis. Numerous researches indicate that in the process of generation of sperm nuclear, histone transmits into protamine from intermediate basic proteins. This process often plays a key role in spermatogenesis. In this process, that sperm chromatin lost prevention is easily impaired, could result in sperm defection. In our study, the Acridine Orange was used to identify the DNA intact of sperm. Under the observation of fluorescence microscope, when the fluorescence material bins to double string DNA, the green fluorescence was shown, and when the AO binds to single string DNA, red fluorescence could be seen. Our result showed that the positive percent in the test and control group was 80% respectively. Aniline blue staining was used to assess the sperm nucleus maturity. These results indicated that the positive rate of the transition of nuclear protein was up to 66.5% in the sperm with abnormal morphology, which was significantly higher than that rate of 20.35%in the abnormal morphology. In all, the abnormal nuclear of sperm will lead to the increasing of sperm malformation, and subsequently result in the degrade of fertility capacity. The development of assistant reproduction technology (ART) open up a new area of therapy male infertility. Our result indicates that the proportion of sperm with normal morphology related to the rate of successful ART. When the proportion declined to 5%, the rate of successful ART significantly declined. Although ICSI permit the entrance of taratosperm into oocyte, the rate of oocyteactivated, potential of embryo survive and the proportion of abortion. all increase. Nowadays sperm separation was widely used to select high quality sperm. In our study, the advantage and disadvantage between swim-up and Percoll protocol was examined. The result indicated that the percentage of sperm with normal morphology selected by swim-up and percoll were significantly different, and the swim-up was better than Percoll protocol. Sperm head is consisted of condensed sperm nuclear and acrosome , the former is a agent of genetic substance, the latter contains diverse hydrolytic enzyme. In the process of infertility, when sperm happens to oocyte, acrosomal membrane and sperm plasma membrane interact and have alteration of structure, which could make membrane permeability increased and hydrolytic enzyme released. Subsequently, zona pellucida (ZP) will be resolved. sperm penetrate ZP and enter the oocyte. Finally, fertility is completed through cooperation of adequate sperms . Furthermore, posterior ring of sperm head is considered as the sperm-oocyte binding point, and play a important role in sperm penetrating oocyte membrane. Mitochondria and axonemal microtubules ,they are regarded as equipment of providing energy and structure basement of motion, are lie in sperm nick ,mid-piece and tail. Our results observed with electron microscope showed vacuole acrosome often appeared in morphologically normal sperm, vesicle which came from translocation of acrosome was hollow. Meanwhile, wave alteration of acrosomal membrane happened. Sperm head desquamated, chromatin condensed abnormally. The alteration of vacuole or granule appeared. taper sperm,large round sperm,amorphous sperm were frequently observed in sperm head defection. Abnormal mitochondria was appeared that different size, abnormal morphology,inhomogeneous distribution or abnormal arrangement. There is significantly correlation between sperm morphology and its function. Therefore, any morphological defection of sperm will lead to decrease of sperm function which could influence on male fertility.
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