The Protective Effect Of Taurine On The Toxic Acute Renal Injury In Rats And Its Possible Mechanisms

Objective To observe whether melatonin provides the protective effect on g-entamicin-induced toxic acute renal injury and investigate its possible mechanisms.Methods Twenty-four adult Wistar rats were divided into three equal groups r-andomly. In each group, there were eight rats. One half were male and the otherhalf were female. (1) melatonin-treat group (MLT+GM group): given subcutaneousinjection of GM(70mg/kg/12h) for four days; and given intraperitoneal injection ofMLT (5mg/kg/day) 1 hours before first GM injection each day. (2) GM group:given GM injection as the GM+MLT group and given the same amount of salineinstead of MLT; (3) Cont group: given the same amount of saline instead of GMand MLT. In the experiment, the weight,the urine volume for twenty-four hours,blood ureanitrogen(BUN),serum creatinine (Cr),the activities of N-acetyl-β-D-glucosaminidase in urine,the levels of malondialdehyde(MDA) in serum and kidney tissue,the activities of superoxidedismutase (SOD) and glutathione peroxidase (GSH-Px) in serum and kidney tissue were obser-ved; meanwhile renal histomorphological changes were observed through naked eyes and micr-oscope. Immunohistochemical expression of inducible nitric oxide synthase in kidne-ys was also observed in the experiment.Results①In the GM and GM+MLT groups, before and after giving drugs,the body weights were descend obviously (t=4.95～5.40, p＜0.01), and urine vo-lume for twenty-four hours were increased significantly (t=-5.43～-4.57, p＜0.01);②The BUN, SCr and NAG levels of the GM+MLT group were significant-ly lower than those of the GM group(t=3.91～9.55, p＜0.01);③MDA levelsof serum and homogenate were obviously lower in GM+MLT group than that inGM group,while decrease of activities of SOD and GSH-Px were ameliorated byMLT(t=-10.41～5.23, p＜0.01);④Microscopically, the GM group revealed s-evere histopathological damages, while the GM+MLT group revealed only mild ch-anges(x~2=20.464, P＜0.01);⑤Immunohistochemically, the expressions of iNOS of the renals in the GM group were much more obvious than that in the GM+MLT group(x~2=19.908, P＜0.01).Conclusions①MLT is effective in protecting the kidneys' morphous and f-unction of rats from gentamicin-induced acute renal injury.②The interaction b-etween gentamicin and phospholipids of biological membranes,destruction of cytol-ysosome,production of ROM and its induced lipid peroxidation,increase of iNOSsynthesis and release play an important role in pathogenesis of gentamicin-inducedtoxic acute renal injury, gentamicin-induced toxic acute renal injury is probably t-he result of the comprehensive effect of the above mechanisms.③MLT mayprotect kidneys from gentamicin-induced acute renal injury by direct and indirect anti-oxidation.