OBJECTIVETo study the effect of Poria cocos (Pcs) in preventing acute rejection of rats after renal transplantation and its mechanism.

METHODSRat orthotopic renal transplantation model was performed with Wistar rat as donor and SD rat as donee. All donees were divided into 4 groups, 10 in each group, before transplantation. They were treated respectively with normal saline 5 mL x kg(-1) x d(-1) (A), Pcs 25 mg x kg(-1) x d(-1) (B), Pcs 50 mg x kg(-1) x d(-1) (C) and ciclosporin A (CsA) 5 mg x kg(-1) x d(-1) (D) by intragastric administration. The renal allograft survival time (ST) was recorded, and the serum levels of creatinine (SCr), interleukin-2 (IL-2), gamma-interferon (gamma-IFN), CD4+, CD8+ lymphocytes percentage, CD4+/CD8+ ratio, as well as the pathologic changes were observed one week after transplantation.

RESULTSST of the renal graft in Groups C and D was significantly longer with pathologic change evidently less than those in Groups A and B (P<0.01), and the ST in Group C was shorter that in Group D (P<0.05). Changes of renal function and urine volume were identified to the pathological change of graft, the initiating time of renal dysfunction was later in Groups C and D than that in Groups A and B. Serum levels of IL-2, IFN-gamma and CD4+ percentage in Group C were significantly lower than those in Groups A and B, but higher than those in Group D respectively (P<0.05 or P<0.01), while CD8+ percentage in Group C was significantly lower than that in Group A (P<0.05), but insignificantly different to that in Groups B and D (P>0.05).

CONCLUSIONPcs shows good dosage-dependent effect in suppressing acute rejection of renal transplantation, but the effect is inferior to that of CsA.