Effects of the different sections of receptor-associated protein on the expression and distribution of TRPC6,synaptopodin and podocalyxin in passive Heymann nephritis / 中华肾脏病杂志

ABSTRACT

objective To investigate the effects of different sections of receptor associated protein (RAP) on the expression and distribution of TRPC6,synaptopodin and podocalyxin in passive Heymann nephritis(PHN). Methods Male Sprague-Dawley rats were injected with three kinds of antisera (anti-RAP full-length serum,anti-RAP N-terminal serum and anti-RAP C-terminal serum)to establish three kinds of PHN models.The control group was injected with normal rabbit serum.The quatitation of 24 h urinary protein,serum albumin and creatinine were taken before injection and one week after PHN model successfully induced.The histopathologic changes of renal tissues were observed by light microscopy.The expression and distribution of TRPC6,synaptopodin and podocalyxin in glomerular podocytes were observed by laser scanning confocal microscopy and analyzed by fluorescence quantitative software after indirect immunofluorescence double staining.Results The quantities of 24 h urinary protein in the three model groups were significantly higher than those of themselves before injection and control groups (P0.05).The expression of TRPC6 in podocytes was higher in the PHN model groups than that of control group.Fluorescence intensity of TRPC6 in RAP full-length group was stronger than that in RAP N-terminal or C-terminal groups.The expressions of synaptopodin and podocalyxin distributed along the glomerular basement membrane as spot,discontinuous short line and defect of some segments,and were lower in three PHN groups than those of control group.Fluorescence intensity of synaptopodin and podocalyxin among three PHN groups had no differences. Conclusions RAP full-length and N-terminal or C-terminal parts can increase the expression of podocyte TRPC6,but decrease the expressions of synaptopodin and podocalyxin,and alter their distribution,which may be associated with the proteinuria,however,their role in the PHN pathogenesis needs further study.