AIM: To investigate the effect of tetramethylpyrazine on hepatic/renal ischemia and reperfusion injury in rats. METHODS: Hepatic/renal funclJon, histopathotogical changes, and hepatic/renal P-selectin expression were studied with biochemical measurement and immunohistochemistry in hepatic/renal ischemia and reperfusion injury in rat models. RESULTS: Hepatic/renal insufficiency and histopathological damage were much less in the tetramethylpyrazine-treated group than those in the saline-treated groups. Hepatic/renal P-selectin expression was down regulated in the tetramethylpyrazine-treated group. CONCLUSION: P-selectin might mediate neutrophil infiltration and contribute to hepatic/renal ischemia and reperfusion injury. Tetramethylpyrazine might prevent hepatic/renal damage induced by ischemia and reperfusion iniury throuclh inhibition of P-selectin.
To observe the expression of P-selectin and the localization of dendritic cells (DCs) in human kidney with IgA nephropathy, and to evaluate their function in human renal tubulointerstitial lesions and renal dysfunction, 45 biopsy specimens of patients with IgA nephropathy were divided into 3 groups according to the degree of renal tubulointerstitial lesions: i. e. mild group ( n =29), moderate group ( n =10), severe group ( n =6). Ten normal renal tissues severed as control. The expression of P-selectin was analysed by immunohistochemistry. CD1a +CD80 +DCs were investigated by double immunostaining method and the images were analyzed with Axioplan 2 microscopy. The experimental results showed that (1) P-selectin was not expressed in normal controls, but presented mainly in renal tubular epithelial cells, which was greater in severe group than mild and moderate groups. The expression of P-selectin was associated with the degree of renal tubulointerstitial lesions. (2) CD1a +CD80 +DCs were hardly observed in nomal renal tissues, but in renal tissues of patients with IgA nephropathy, CD1a +CD80 +DCs were mostly found in renal tubulointerstitium. Also the distribution area, number and density of CD1a +CD80 +DCs in severe group was much more than other groups, which was associated with the degree of renal tubulointerstitial lesions and the lever of serum creatine. The distribution of CD1a +CD80 +DCs was associated with the expression of P-selectin in patient′s renal tubulointerstitium. The present study demonstrated that P-selectin and DCs might play an important role in renal tubulointerstitial lesions of IgA nephropathy, and DCs recruited into the renal tissues with IgA nephropathy might be mediated by P-selectin.