Effect of sirolimus on renal ischaemia/reperfusion injury in normotensive and hypertensive rats

Background. Renal ischaemia/reperfusion (I/R) injury and hypertension represent major alloantigen-independent factors contributing to the development of chronic allograft nephropathy of renal allografts. In the present study, we investigated the effect of the anti-proliferative immunosuppressant, sirolimus (SIR), in a model of accelerated renal injury in hypertensive transgenic rats (TGRs). Twenty anaesthetized uninephrectomized TGRs with renin overproduction [TGR(mREN2)27] and 20 normotensive Han SD (SD) rats as genetic controls had their renal pedicles clipped for 45 min and were subsequently treated with either SIR (0.5 mg/kg per day, orally) or placebo (n=10 in each group) for 16 weeks, after which time the kidneys were harvested for morphological and immunohistochemical analysis. High-renin hypertension aggravated the functional and structural changes induced by I/R in SD animals: both SIR-treated and untreated TGRs exhibited significantly greater proteinuria and suffered from more severe glomerulosclerosis (P