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The protective effects of zinc on liver injury induced by D-galactosamine (GalN) were investigated in rats in vivo and in vitro. Zinc supplementation (50 mg/kg/d) for 5 d of rats treated with GalN (1.5 g/kg, ip) could reduce their mortality rate, restore liver pathomorphological changes, maintain zinc content, inhibit the lipid peroxidation, hasten the protein synthesis, and improve liver function. In vitro, zinc supplement could abate the death of GalN-intoxicated hepatocytes, decrease malonaldehyde (MDA) content, and maintain reduced glutathione (GSH). It is concluded that zinc has protective effects on GalN-induced liver damage. Its effects may be owing to inhibition of lipid peroxidation and hastening of protein syntheses.

The changes in trace elements, free radicals, and neurophysiological function were investigated in rats with liver damage induced by D-galactosamine (GalN). The elevated results showed that all the parameters related to free radical metabolism changed after administration of GalN. Relative free radical concentration, malonaldehyde (MDA), and oxidized glutathione (GSSG) elevated, but reduced glutathione (GSH) decreased. Concurrently, zinc, copper, manganese, and selenium contents in liver were significantly reduced, whereas iron was elevated. In rats with hepatic encephalopathy (HE) owing to fulminant hepatic failure (FHF) induced by a high dosage of GalN, the latencies of VEPs were delayed. Moreover, there is a correlation between Zn content of brain and the latencies of VEPs. The results of this study suggested that lipid peroxidation by free radicals might be responsible for GalN-induced liver damage in which trace elements were involved, and that change in brain Zn might play a role in the neural inhibition of HE owing to FHF.

Hemoglobin Jianghua (Hb Jianghua) is a new fast--moving hemoglobin variant found in China, being named after the county where it was detected. Having its primary structure analysed, we report in this paper the results of studies on its function. The absorption spectrum, response to allosteric effectors and oxygen equilibrium of the chromatographically purified Hb Jianghua showed its characteristics similar to those of purified Hb A. Its alkaline Bohr effect was normal. This indicates that a substitution of isoleucine for the 120th lysine residue of the beta chain had no significant influence upon the function of Hb molecule.