[Medicine S inhibits class II MHC expression of intragraft renal in rats]

The Purpose of this study was to address the mechanism of medicine S which has anti-rejection effects of renal allografts in rats. Kidney transplantations were performed from SD to Wistar strain (allogeneic) and from Wistar to Wistar (Isograft) using the same modified technigue described by Fabre and kamada. Experimental rats were divided into five groups. Group I (Isograft group) and group II (allograft group) as controls were not treated with medicine. The others were allograft groups which received medicine S, Cyclosporine A, and low-dose Cyclosporine combined with medicine S, respectively. Renal function and resultant morphology changes were assessed 2, 4 weeks after transplantation. All sections of kidney grafts were stained with monoclonal antibody class II MHC (OX6), and then the surface densities of positive staining were quantified by computer image analysis. The level of molecular expression in group II was significantly increased (7.61 +/- 0.57 vs 0.51 +/- 0.2 of group I, P < 0.01). In groups I and IV, the molecule of expression was reduced, compared with the groups II, III and V (P < 0.05). The results suggest that medicine S decreases the level of class II MHC expression and medicines combined with lowe-dose cyclosporine is more effective than cyclosporine alone.