Effects of 17β-estradiol on cell activity,cell cycle and ultrastructure of AC in vitro

The expression of estrogen receptor α,β was detected in the astrocytes in vitro by immunofluorescence analysis and the optimal concentration of lipopolysaccharide stimulating AC was obtained by CCK-8 assay.It was on this basis that the effects of 17β-estradiol on cell activity,cell cycle and ultrastructure of actrocytes(AC) were observed.The results were as follows:compared with the control group,significant elevation of the cell activity(P0.05)and the percentage in G2+S phase of AC(P0.05)were discovered at 48 h after treatment with 10 nmol/L E2,whereas 100,1 000 nmol/L E2 reduced markedly the cell activity(P0.05)and 100 nmol/L E2 also decreased the percentage in G2+S phase(P0.05);24,48 and 72 h after treatment with 100 nmol/L E2,the cell activity and the percentage in G2+S phase in all experimental groups lowered and maximal inhibition was observed at 48 h(P0.05);48 h after E2 treatment,10 nmol/L E2 increased number of mitochondria,caused more nucleus division and maintained the normal structure of mitochondria and rough endoplasmic reticulum,100 nmol/L E2 resulted in swelling or vacnolation in mitochondria and made rough endoplasmic reticulum expand or rupture.The results suggest that low dosage of E2(10 nmol/L) can promote AC proliferation,while higher dosage E2(100,1 000 nmol/L)can inhibit AC proliferation.