Effects of different dose of gamma rays on renal tubule epithelial cells: proliferation and function

Objective: To study changes of proliferation and function of primary renal cells after being exposed to different dose of gamma rays. Methods: Primary renal cells were cultivated by means of mechanical separation and enzyme digestion. Cells were subjected to 0, 1, 5 and 10 Gy gamma rays, and proliferation of cells was detected by MTT, expression of mRNAs determined by RT-PCR, expression of proteins by Western Blot. Results: Logarithmic growth phase of cells was delayed by 1 Gy gamma rays, and restrained by 5 Gy and 10 Gy gamma rays. The expression of mRNA of Na+, K+- ATP enzyme, 1α-hydroxylase and 24-hydroxylase was significantly decreased by 1 Gy, 5 Gy and 10 Gy gamma rays. The expression of mRNA and protein of TGF-β was significantly promoted by 1 Gy, 5 Gy and 10 Gy gamma rays. The expression of protein of OPN was promoted by 1 Gy gamma rays, and inhibited by 5 Gy and 10 Gy gamma rays. Conclusion: Irradiated renal cells with different dose of gamma rays can significantly suppress its proliferation, promoting it turn into fibroblast, and resulting in accumulation of matrix proteins by way of increasing TGF-β secretion. This effect is dose-dependent. (authors)