ABSTRACT

Paracetamol (Acetaminiphen) in toxic doses caused electrolyte imbalance, anaemia and oxidative damage, which manifest itself as renal failure and hepatic centrilobular necrosis. This study aimed to investigate the effect of L-arginine on some haematological and biochemical indices of paracetamol- intoxicated Wistar rats. Twenty-five wistar rats with an average weight of 88.4g were randomly allocated into five groups of 5 rats each. Group A (control) fed with feed and water, Group B (L-arginine) administered 60 mg kg body weight, Group C (Paracetamol) administered 1000 mg kg body weight, Group D (L-arginine/paracetamol) administered 60 mg kg and 1000 mg kg body weight and Group E (High dose L-arginine/ paracetamol) administered 120 mg kg b-wt and 1000 mg kg body weight. Treatment was daily, per oral and lasted for 14 consecutive days. Results of biochemical parameters (Total-bilirubin, Creatinine and MDA) showed significant increase (p<0.05) in paracetamol treated groups when compared to the control. However, treatments with L-arginine did not abate their level. Results of K⁺ and Cl^- showed significant (p<0.05) reduction in groups treated with paracetamol when compared with the control. Treatment with L-arginine, for K⁺, at different doses after paracetamol intoxication was insignificant while Cl^- was increased by treating with L-arginine dose dependently. RBC value in all treated groups showed significant (p<0.05) decrease when compared to the control. Hb and PCV values were non-significant (p>0.05) in the paracetamol treated group when compared to the control. L-arginine treated group for PCV was also non-significant (p>0.05) when compared to the control. However, Hb level of L-arginine control group and the treated groups showed significant (p<0.05) increase when compared to the control. WBC level showed significant (p<0.05) increase in paracetamol group when compared to the control. Treatment with L-arginine showed significant (p<0.05) reduction when compared to the control. Glutathione peroxidase (GPx) activities in the Liver and Kidney of paracetamol group were significantly (p<0.05) reduced when compared to the control. Treatment with L-arginine showed significant (p<0.05) increase both in the Liver and Kidney when compared to the control and this confirmed the antioxidant properties of L-arginine. Catalase activity in all treated groups showed significant (p<0.05) decrease both in the Liver and Kidney when compared to the control. AST and ALT activities showed significant (p<0.05) increase in paracetamol group when compared to the control. However, treatment with L-arginine showed significant (p<0.05) decrease in the activity. ALP activity showed significant (p<0.05) reduction in paracetamol group when compared to the control. Treatment with L-arginine also recorded significant decrease when compared to the control. Intoxication with paracetamol at 1000 mg kg body weight showed a reduction in weight gain (12.04 compared to the control (25.46±4.91) and arginine group (24.70±3.95). Histological examination reveals that treatment of paracetamol intoxicated groups with L-arginine at 60 mg kg showed normal hepatic histo-architecture. However, treatment with L-arginine at 120 mg kg presented a coagulative necrosis of the centrilobular and mid-zonal hepatocytes with moderate infiltration of phagocytic mononuclear leukocytes. Kidney section of all treatment groups showed normal renal histo-architecture, with normal renal tubules. Sections of the testis collected from all treatment groups showed normal testicular histo-architecture with normal seminiferous tubules. This study therefore suggests that L-arginine could be used as a therapeutic agent in restoring paracetamol induced haemato, hepato and renal toxicities in rats.