The Biological Characteristics And Gene Expression In Epithelial Cell Of Caput,Corpus And Cauda Of Sheep Epididymidis

Epididymis is an important reproductive organ of domestic animals,which has the functions of storage,transport and promoting sperm maturation.But the functions of different parts have obvious differences.The biological characteristics and gene expression of epithelial cells in different parts of epididymis in sheep were studied.It lays the foundation for further study on the regulation mechanism of epididymis function in sheep.The results are as follows:1.Isolation,culture and growth characteristics of epididymal epithelial cells.The epithelial cells of caput,corpus and cauda of the epididymis in sheep were isolated by enzyme digestion.The culture conditions were RPMI1640 medium containing 10%fetal bovine serum,5μg/m L transferrin,100nmol/L androgen,50 u/m L penicillin and 50μg/m L streptomycin,37℃,5%CO₂.The results of cell growth curve showed that the proliferation rate of epithelial cells in the caput of epididymis was significantly higher than that in the corpus and cauda of epididymis from days of 2 to 4（P<0.01）,while the proliferation rate of epithelial cells in caput and corpus of epididymis was significantly higher than that of cauda at 5 day（P<0.01）.The results of cell cycle detection showed that the number of epithelial cells in the caput,corpus and cauda of epididymis in S+G2 phase was 49.23%and51.79%,respectively,which was significantly higher than that in the epididymis cauda（42.78%,P<0.01）.There was no significant difference between the caput and corpus of epididymis.Apoptosis of cells in passage 2 showed that the survival rate of epithelial cells in the caput and corpus of epididymis was 88.23%and 88.30%,respectively,which is significantly higher than that in the epididymis cauda（78.89%,P<0.01）,but there was no significant difference between the caput and corpus of epididymis.2.Expression characteristics of epididymal epithelial related functional genes（P66shc,P34h,Serpina1,Ak1,Clu）.The results of real-time quantitative PCR showed that expression of P66shc,P34h and Serpina1 genes had significant downward trend from the caput to the cauda of epididymis,and the caput was significantly higher than the corpus（P<0.01）,and the epididymis corpus was significantly higher than the epididymis cauda（P<0.01）.AK1 expression in the epididymis caput was significantly higher than that in the epididymis corpus（P<0.05）.The expression of Clu in the epithelial cells of the caput and corpus of epididymis was significantly higher than that in the epididymis cauda（P<0.01）,but there was no significant difference in the expression between the caput and corpus of epididymis.3.Expression characteristics of antioxidant enzymes genes（GPXs and PRDXs）in epididymal epithelial cells.The results of real-time quantitative PCR showed that there was no significant difference in the expression of Gpx1 and Gpx4 in the epithelial cells of the caput,corpus and cauda of epididymis.The expreesion of Gpx2 and Gpx3 in epididymis corpus was significantly higher than that in caput and cauda of epididymis（P<0.01）,but there was no significant difference between corpus and cauda of epididymis（P>0.05）.And the expression of Gpx2 and Gpx3 in epididymis caput was lower than that in epididymis corpus,but there was no significant difference between corpus and cauda of epididymis（P>0.05）.The expression of Gpx5 in epididymis caput was significantly higher than that in the corpus and cauda of epididymis caput（P<0.01）,but there was no difference between the corpus and cauda of epididymis.The expression of Prdx1 and Prdx4 had no significant difference among the epithelial cells of the caput,corpus and cauda of epididymis.The expression of Prdx2 and Prdx3 in caput and corpus of epididymis was significantly higher than that in epididymis cauda（P<0.01）,but there was no difference between caput and corpus of epididymis.The expression of Prdx5 in the epididymis caput was significantly higher than that in the corpus and cauda of epididymis（P<0.01）,but there was no significant difference between the corpus and cauda of epididymis.The results showed that there were significant differences in the expression of antioxidant enzyme genes in different parts of epididymis in sheep.In conclusion,the obvious differences in biological characteristics and related gene expression of epithelial cells in different parts of sheep epididymis were observed,which may be closely related to the function of different parts of sheep epididymis.