Effect of calcitriol and aminoguanidine on acute renal allograft rejection in rats

Objective To explore the methods of induced tolerance in rats renal allotransplantation and provide a theoretical basis for clinical use. Methods Orthotopic renal transplantation from Wistar rats to SD rats was used as a model of study. The experimental rats were divided into the following groups: Group Ⅰ as isotransplantation control group, Ⅱ as acute rejection control group, respectively. Group Ⅲ, Ⅳ and Ⅴ were treated with aminoguanidine (AG), calcitriol and the combined use of calcitriol and AG, respectively. The survival time of recipients was observed, meanwhile, the donor specific mixed lymphocyte reaction (MLR) and concentrations of IFN-γ, Ca 2+ and P 3+ in serum were measured. HE staining inspected all specimens of kidney grafts. Results The recipient survival time in the groups Ⅰ, Ⅱ, Ⅲ, Ⅳ and Ⅴ were ( 9.1 ± 1.9 ),( 5.3 ± 0.8 ),( 9.7 ± 2.1 ),( 8.6 ± 1.6 )and( 12.9 ± 3.4 )days, respectively. There was significant difference in recipient survival time between group Ⅴ and group Ⅱ, Ⅲ and Ⅳ (P0.01 vs group Ⅱ and Ⅳ, P0.05 vs group Ⅲ). Five days after operation, the proliferation of anergic cells in the MLR was strongly inhibited (P 0.01 ), and the level of IFN-γ in serum was obviously decreased (P 0.01 ). The recipients' renal function was obviously improved (P 0.01 ) and the grades of acute rejection of allgrafts were mitigated (P 0.05 ), in groups Ⅲ, Ⅳ and Ⅴ as compared with group Ⅱ. The results of group Ⅴ were more satisfactory than in group Ⅲ and group Ⅳ. The levels of Ca 2+ and P 3+ in serum had no significant difference among them. Conclusion Calcitriol and AG have a synergistic effect and can achieve better effects on the inducement of immunological tolerance and the improvement of graft survival.