protective effect of L-tryptophan versus alpha lipoic acid against L-arginine-induced experimental acute pancreatitis in albino rats

ABSTRACT

This study was conducted to investigate the possible protective effects of L- treptophan "a precursor of melatonin" and alpha lipoic acid against L- arginine-induced experimental acute pancreatitis in albino rats. Fourty adult male albino rats [200- 250g] were randomized into 4 groups [n= 10]. Group I, the control group was given 0.9% saline intraperitoneally [i.p]. Group II, was given 500 mg/lOOg L-arginine [i.p] as a single dose to induce acute pancreatitis. Group III was given 250mg/kg L-tiyptophan [i.p] 30 mm prior to L- arginine injection. Group IV was given 50mg/kg alpha lipioc acid [i.p] 30 mm prior to L-arginine. Before scarifice, blood samples were obtained from all groups to assay serum amylase and interleukin 6. Animals were sacrificed after 6 hours. For the histopathological study, pancreatic tissue was prepared for histological [H and E, PAS] histochemical [Tween stain for lipases] and immunohistoehemical [Bax stain for apoptosis] techniques. Both qualitative and quantitative analyses were done to assess the degree of acinar cells affection. It was revealed that serum amylase and interleukin 6 in group II rose rapidly. Microscopically, severe acinar cells degeneration, interstitial edema, diffuse bleeding and inflammatory infiltration were demonstrated. These changes were markedly improved with the administration of both L- tryptophan and alpha lipoic acid. It was concluded that both L- tryptophan and alpha lipoic acid reduced the effects of L-arginine-induced acute pancreatitis with better protection achieved by L-tryptophan administration