【關鍵詞】 失重；成骨細胞；整合素類
【Abstract】 AIM: To investigate the expression of integrin subunits in osteoblasts during simulated weightlessness induced by clinostat. METHODS: Calvarial osteoblasts of neonate rats were cultured under conditions of normal gravity(1G) and simulated weightlessness induced by clinostat respectively. The total RNA in cells was isolated in different time points (24, 48, 72 h). Reverse transcription PCR analysis was made to examine the gene expression of α5, αv and β1 integrin subunits. Each value was normalized against that of βactin mRNA. Moreover, the protein expressions of all kinds of integrin subunits were also detected with Western blotting. RESULTS: The gene expression of 3 integrin subunits started to change from 24 h of rotation in clinostat but not in stationary cultures. The expression of integrin α5 mRNA decreased at 24, 48 and 72 h of rotation by 11.3%, 18.7% and 9.8%, respectively. The same trend was saw in the expression of integrin αv mRNA as 23.0%, 12.3% and 16.7%, respectively. Moreover, the expressions of integrin β1 mRNA in different periods were also declined by 15.3%, 11.4% and 26.4%, respectively. The differences were all statistically significant as compared with controls (P