ABSTRACT
Ischemia reperfusion is a common leading cause to acute renal failure. Cellular mechanisms include cell adhesion, cell infiltration and generation of oxygen free radicals, and inflammatory cytokine production have been identified, however, the exact causes remain unclear. The aim of the present study was to investigate the role offibronectin [FN], interleukin-18 [IL-18] and serum ferritin in a vivo model of unilateral ischemic and/or reperfused kidney in the rat. In addition, the effects of different durations of ischemia, with or without reperfission on the previous parameters were assessed. This study was carried out on 40 male albino rats divided into 4 groups [10 rats/each]. They were group I: rats were subjected to renal ischemia for 40 minutes without reperfusion; group II: rats were subjected to permanent renal ischemia for 24 hour; group III: rats were subjected to renal ischemia for 40 minutes followed by 24 hour of reperfusion and group IV: sham operated rats. Renal ischemia was induced by clamping the renal artery and vein for 40 or 24 hour mm whereas the contralateral kidney is left intact. At the determined time of sacrifice the blood was collected by cardiac puncture and serum was separated. Both kidneys [left postischemic and right contralateral] were excised and frozen at-80 C for biochemistry. The kidneys were homogenized and used for estimation of fibronectin and IL-18 by EL1SA and serum samples were used to estimate the ferritin by ELISA. The mean value of FN and IL-18 was peaked at 24 h after permanent ischemia in group II, it was significantly high compared with the other studied groups. Forty minutes of ischemia without reperfusion was associated with increased level of FN and IL-18 compared with 40 minutes ischemia with subsequent reperfusion. However, the difference was not statistically significant. Forty minutes ischemia without repeifusion in group I was associated with the highest signicant increase in serum ferritin level. In conclusion, ischemia with or without reperfusion was associated with upregulation of the detected extracellular matrix proteins; spec [flcally FN as well as the detected cytokine; IL-18 from renal tissues. However, the highest increase in these two parameters was observed in permanent ischemia [for 24h] rather than transient ischemia [40 minutes]. The elevated level of FN in permanent ischemia explains its possible role in the regeneration of the damaged kidney and/or fibrosis. Reperfusion has no prominent effect on renal FN and IL-18 levels. Thus, time of ischemia may be the most important determinant for higher FN and 11-18. Moreover, this study had showed that serum ferritin increased significantly in transient ischemia without reperfusion which indicates its role as an acute phase reactant in a response to ischemia