| Apoptosis is a form of death which occurred physiologically and gradually in multicellular organisms under control of Intrinsic and extrinsic factor,is a main character of growth and development of multicellular organic body. The hair follicle is a very complicated organ,cycle re-growth is its main character. Hair growth cycle may divide into the vegetal period,draw back the departure date and stops the time three stages in a lifetime of mammal. Seiberg consider apoptosis having a close relation with the hair growth cycle after his study based on other persons study.In this study structure of sheep skin tissue,thickness of epidermis and Leather of skin,distribution of apoptosis cell,expression of Bcl-2∕Bax protein and chainging rule of expression of Bcl-2∕Bax mRNA were studied by H·E stain,DNA in situ labeling,Immunohistochemistry and PCR,meanwhile the relationship of the hiar growth cycle and cell apoptosis,the relationship of cell apoptosis and season changes, and rule of hair follicle cell apoptosis were investigated. The main experimental results are as follows: 1. The morphologic change as apoptosis in skin and hair follicle of Mongolia sheep during deferent season(1)There was no changes observed in the structure of sheep skin in different seasons,while the thickness of skin is changed with the season changes.Epidermis is thickest in Jun in a year and thinnest in December;Leather is thickest in August in a year and thinnest in October. The analysis of average thickness of H·E stained skin samples showed that the epidermis thickness change of Mongolia sheep is a continuous process,and it have germane relationships with season cycle. The thickness of corium is easy to change with the season changes.(2)The results of TUNEL staining and DNA in situ labeling experiment showed that the apoptosis cell mainly in hair follicle,it could happen at any hair growth time,and number,degree of apoptosis cell varies with their season;The number of apoptosis cell is detected highest in Jun,lowest in October,then increase again to form a《∽》change curve. The thickness of epidermis was negatively related to number of apoptosis cell,skin attenuation begins from April and become thinnest in May to Jun. This changing rule of skin is consistent to the time of seasonal hair exchange of domestic animals.(3)The results of electron microscope showed that the apoptosis do not often happen in the epidermis granular layer of Mongolian sheep,and no significant changes was observed in Ultrastructure of epidermis.2.The skin Bcl-2/Bax apoptosis protein change of Mongolia sheep in deferent season(1)The results of Immunohistochemistry showed that the rate of positive cell expressing Bcl-2 is highest in December,lowest in Jun,the change of Bcl-2 positive cell rate in a year form a《ν》shape change curve.(2)The rate of positive cell expressing Bax is to increase with changes of month, and gradually decrease after reach highest level in Jun. The highest expressing rate of BaxBcl-2 and lowest expressing rate of Bcl-2 appear in Jun simultaneity, this indicate that high level of apoptosis may occurred in this time.(3)The expressing positive cell ratio of Bcl-2/Bax is to increase gradually after a period of decrease to form a V shape change curve, it reach highest level in April, and then decrease to lowest level in Jun, the high level of apoptosis occurred in this period. This result indicate that vegetal period draw back the departure stops the time were negatively related to Bcl-2 and Bax expression,it is a pair of positive negative regulate gene of apoptosis. The former restrain cell apoptosis,prolong the cell growth cycle,increase cell accumulation rate,the latter not only accelerate the cell apoptosis but also regulate cell apoptosis with the former.3. The skin Bcl-2/Bax mRNA expressing change of Mongolian sheep in deferent season(1)The PCR results showed that the Bcl-2 mRNA expression is consistent to the results of Immunohistochemistry and stain experiment in all the hair follicle growth cycle, indicate that Bcl-2 mRN expression have a significant affect on Bcl-2 protein expression and cell apoptosis.(2)The PCR results showed that the mRNA expression of Bax gene showed a wavilness dynamic balance,and have no relation to Bax protein expression, this indicate that Bax and mRNA expression not happen simultaneity.(3)It is found that by data analysis,Bax expression is negatively related to Bcl-2 expression,this indicate that the cell apoptosis regulation is achieved mainly by Bcl-2 gene,and Bax gene regulate the cell apoptosis by taking part in Bcl-2 gene regulation. The mechanism of mutual restriction and mutual influence between Bcl-2and Bax result in a stable regulation.Conclusion,cell apoptosis has a close relation with the Bcl-2 and Bax expression,Bax gene accelerate apoptosis,and expression of Bcl-2 and Bax play a important rule in the course of cell apoptosis. Above results laid a solid theory foundation for the farther study on mechanism of cell apoptosis gene regulation,obtained a reliable experiment results about relationship between apoptosis and hair growth and moult,relationship between Bcl-2/Bax expression and follicle apoptosis,mechanism of hair growth cycle,those experiment data have a theory value for research on personal controlled new technique of hair growth and moult.
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