[Effect of PKC inhibitor on renal podocyte slit diaphragm protein expression in exhausted rats]

Objective: To investigate the expression level of podocyte slit diaphragm protein in rats after one-time exhaustive exercise, to explore the effect of PKC inhibitor on the protein expression level, and to reveal the mechanism of PKC in the formation of exercise-induced proteinuria. Methods: Thirty male SD rats were randomly divided into control group (C), exercise group (E) and exercise combining with PKC inhibitor group (EPI), with 10 rats in each group. Rats in group E and EPI performed one single bout of exhaustive exercise (25 m/min), rats in group EPI were intraperitoneally injected with a PKC inhibitor (chelerythrine, 5 mg/kg) 1 day and 1 hour before exercise respectively, while rats in group C and E were injected with the same volume of saline. Results: ①Compared with group C, the levels of urine protein, uric acid, urine sugar, blood urea, and blood uric acid of rats in group E were increased significantly (P＜0.05), the level of blood glucose was reduced significantly (P＜0.01), and renal ROS production was increased significantly (P＜0.01). The expressions of nephrin and podocin protein in renal tissue were decreased significantly (P＜ 0.05), while the expressions of PKC, Nox2, and Nox4 protein were increased significantly (P＜0.05). ②Compared with group E, the levels of urinary protein,urine glucose and blood urea in EPI group were decreased significantly (P＜0.05), the level of blood glucose was increased significantly (P＜0.01), renal ROS production was reduced significantly (P＜0.01). the expressions of nephrin and podocin protein in renal tissues of the EPI group were increased significantly (P＜0.05), while the expressions of PKC and Nox2 protein was reduced significantly (P＜0.05, P＜0.01). Conclusion: One-time exhaustive exercise can down-regulate the expressions of nephrin and podocin through PKC/Nox/ROS pathways in the kidney of rats; PKC inhibitor alleviates the decrease in the expression of podocyte slit diaphragm protein caused by exhaustive exercise, and prevents the occurrence of exercise-induced proteinuria.