Expression Of Apoptosis-related Factors In Corpus Luteum Of Swine

Forming after ovulation,corpus luteum is a temporary endocrine gland and plays an important role in the normal reproductive cycle regulation and the pregnancy maintenance.The phenomenon of degradation exists without conception.Studies have shown that apoptosis is involved in luteal degeneration,and apoptosis occurs in many species during spontaneous and induced degeneration.In this study,porcine corpus luteum was selected as the research object,progesterone assay,TUNEL staining and fluorescence quantitative PCR were used to detect the changes of the apoptotic genes Caspase-3,Caspase-8,Caspase-9,TNF-?,Bcl-2 and Bax in the luteal phase of pigs.Results show:1.Progesterone level:the progesterone concentration in the middle stage reached the peak and was significantly higher than that in other three stages(p<0.05);after the middle stage,the progesterone concentration showed a downward trend,and the concentration of the later stage and the white body was significantly lower than that in the early stage(p<0.05).2.TUNEL staining results:the cells were negative in the early and middle stages,with almost no apoptotic cells observed.3.With the gradual degeneration of corpus luteum,Caspase-3 expression quantity gradually increased,reached the highest value in the white body phase and was significantly higher than that in the other three stages(p<0.05),expression quantity in the later stage was significantly higher than that in the early and middle stages(p<0.05),and there was no significant difference between the two stages(p>0.05).caspase-8 gene expression was observed at all stages.With the gradual degeneration of corpus luteum,the expression level showed an increasing trend,and there was no significant difference between the initial and middle stages(p>0.05).There was no significant difference in the Caspase-9 expression quantity in the early and middle stages(p>0.05),but the expression quantity showed an increasing trend with the luteal degeneration of pigs,and the expression quantity was the highest in the white body stage,and significantly higher than the other three stages(p<0.05).There was no significant difference in TNF-? expression quantity between the early and middle stages(p>0.05).With the gradual degeneration of luteum,the expression quantity showed an increasing trend,and the expression quantity in the white body was significantly higher than that in the later stage(p<0.05).With luteal degeneration,the ratio of Bcl-2/Bax decreased,indicating excessive apoptosis.In this experiment,it can be concluded that there is no significant difference in apoptotic genes Caspase-3,Caspase-8,Caspase-9 and TNF-? expression quantity at the initial and middle stages.With the gradual degeneration of luteum,the expression quantity gradually increase and reach the highest value in the white body stage and are significantly higher than the other three stages.However,with the degeneration of luteum,the Bcl-2/Bax ratio decreases.These genes may be involved in luteal apoptosis in pigs.