[The changes of beta 1-integrin and its mRNA distribution in renal tubular epithelial cells during kidney ischemia/reperfusion injury in neonatal rats].

ABSTRACT

OBJECTIVE: By studying the distribution and expression of beta 1-integrin and its mRNA in renal tubular epithelial cell at different ischemia/reperfusion time phases we probe the role of beta 1-integrin in I/R injury of neonatal animals. METHODS: The neonatal SD rat ischemia/reperfusion model was set up. Immunofluorescent staining and in situ hybridization (ISH) were used to show the distribution and expression of beta 1-integrin with its mRNA in renal tubular epithelial cells and the quantities of beta 1-integrin and its mRNA were counted by ImagePlus-Pro system. RESULTS: 1. beta 1-integrin was located at the basal plasma membrane in normal renal tubular epithelial cells. After ischemia for 0.5 h, the redistribution was not significant. After reperfusing for 0.5 h, beta 1-integrin began to move onto the lateral and apex surfaces of cells. This kind of change was most apparent after reperfusion for 2 h and was accompanied with reduced expression and destruction of renal tubular. No positive dying was seen in the lumen. The regeneration started 24 hours post-ischemia. beta 1-integrin was redistributed onto the basal plasma membrane. After reperfusion for 120 hours, the regeneration ended, but the expression did not gain the normal level. 2. The mRNA of beta 1-integrin was mainly expressed in the cell plasma. Its expression was increased while reperfusion for 0.5 h to 2 h and was still above normal level after 24 h to 120 h of reperfusion. CONCLUSION: The distribution of beta 1-integrin was "depolarized" and its expression was reduced. But the level of mRNA was raised, which indicated that during ischemia/reperfusion injury, there were mechanisms that influenced the distribution and synthesis of beta 1-integrin at the same time.