grape and / or guava seeds extracts on gentamicin induced nephrotoxicity in rats. Fifty seven adult male albino rats were divided into 8 groups. Group 1 (control group) was injected intraperitonealy with saline solution;  groups (2, 3 and 4 were administrated a daily oral dose of grape(40mg/kg/d p.o), guava seeds extracts (300mg/kg/d p.o) or mixture of both, respectively; group 5 was intoxicated with gentamicin (100mg/kg/day i.p); groups (6, 7 and 8) received oral dose of grape and / or guava seeds extracts along with intraperitonealy injection of gentamicin for 10 days. At the end of the experimental period (10 days) rats were scarified and serum was collected for serum creatinine, urea, uric acid and total protein. Parameters of oxidative stress were determined including reduced glutathione (GSH), malondialdehyde, and activity of erythrocyte superoxide dismutase (Cu, Zn-SOD). The results of the present study revealed that treatment of normal rats with grape and / or guava seeds extracts did not show any adverse physiological effects. Gentamicin injection resulted in significant elevation in serum levels of creatinine and blood urea nitrogen.
While, serum total protein was not significantly changed. Administration of gentamicin caused a significant decrement in blood GSH level, erythrocyte Cu, Zn-SOD activity, renal level of reduced glutathione and elevation in level of renal MDA. Treatment with grape and /or guava seeds extracts produced protective effects and attenuated these biochemical changes. The histological examination confirmed the protective effects of grape and /or guava seeds extracts. In conclusion, this study suggested that treatment with grape seeds and / or guava seeds extracts protect against gentamicin induced nephrotoxicity.