Study Of The Skin Structure And Apoptosis Of Mongolia Sheep

In this experiment ,to observe the distrubution of apoptosis cell and analyze the relation of every growth states of hair follicle(HF) and cell apoptosis, the cell apoptosis of HF,the structure and ultrastructure of the epidermis and hair follicle of Mongolia sheep were investigated in different seasons with routine histologic method and in situ end-labeling (terminal deoxynucleotidyl-transferase-mediated dUTP-biotin nick end-labeling (TUNEL) of apoptosis cell and electronic microtechniqu method.The result showed some of the cells of epidermis appeared apoptotic positivity.The number of apoptosis cell of the epidermis began to increase on April,and reach the peak between June and August, and return to previous level between October and December.lt showed reverse relation between the thickness of the epidermis and the number of apoptotic cell.The thickness of the skin became thinner accompanied with the increase of apoptosis of hair follicle ,and became thicker with the reduction of apoptosis of hair follicle .The thickness of the skin began to become thinner on April ,and became the most thinnest between June and August ,then displayed thicker gradually.lt has no distinct difference between the months between 10-12 and 4-5.The apoptosis of HF cell appeared in all periods of HF growth.The cell apoptosis took place in hair matrix cells firstly,and then it happened with the whole HF.The number of apoptosis cell of HF and degree of apoptosis were different in different seasons,which were indicated by that the apoptosis began to increase on April , and apoptosis was active between June and August, whereas it was weak relatively.Observed with electric microscope, it is hair root in the center of HF and was made of hair medulla and hair cortex. The cellar boundary of hair medulla has been disappeared, and the nuclei have been disappeared too. Only lots of homogeneous keratohyaline granules can be seen . HF could also be separated into inner root sheath,outer root sheath and glassy membrane. Inner root sheath could also be divided into cuticle of root sheath ,Huxley's layer and Henry's layer from outer to inner layers. The single layer cells of cuticle of root taking on narrow strip surrounded hair roots ,nuclei also took on strip shape. There is keratohyaline granules of uniform density of electron in cytoplasm, and the density of electron was higher than that of in keratohyaline granules in hair medulla.Huxley's layer contained one or two layer cells,and the cell has much keratohyaline granules with different size.The density of electron of keratohyaline granules is much higher ,and homogeneous was shown .Nuclei are irregular .The chromatin appeared condensation and approached to the edge of nucleir membrane . Henry's layer is a single layer cells. We found no keratohyaline granulesin in cytoplasm and the whole cell is homogeneous.nucleir heterchromatin is flourished.Outer root sheath contained one or two layer cells . The boundary of cell is obscure.There are big vacuoluses in cell. Tonofilaments can be seen in cell occasionally. Glassy membrane is homogeneous structure .The connective tissue and its fibers encompassed glassy membrane. Transverse striation could be seen on the collagenous fiber.