Hepatic injury by acetaminophen (APAP) has been extensively studied, although the alterations of renal functions and arterial blood pressure (ABP) after APAP exposure are still uncertain, and the impact of Nigella sativa oil (NSO) in this case is poorly defined. Sixty adult male albino rats were involved in two sets of experiments. The first was exposed to a single high dose of APAP (2.5 g/kg) orally preceded by 4 ml NSO/kg orally, while the second received 750 mg APAP/kg/day orally for seven consecutive days and was pretreated with 2 ml NSO/kg/day. Proximal tubular injury was assessed by laboratory and histological studies, and arterial blood pressure was recorded in all animals. In both experiments, urinary α-glutathione S-transferase and neutral endopeptidase, and microproteinuria were dramatically increased early indicating glomerulus and proximal tubule dysfunction that was mediated by raising 8-isoprostanes. Concomitantly, urinary albumin, total protein, creatinine, urea, glomerular filtration rate, Na and K levels, plasma creatinine, and urea were all changed significantly after APAP administration. Currently, ABP increased significantly after APAP which was mostly mediated by renal impairment and increased both renin activity and aldosterone secretion. Pretreatment with NSO produced significant normalization of physiological parameters as well as suppression of structural changes. In conclusion, measurement of urinary biomarkers can be considered a powerful tool for early screening of renal injury and alteration of ABP after APAP treatment. Concomitant administration of NSO can counterbalance these detrimental effects.
