The Studies On The Damage Mechanism Of Sub-Chronic Manganism In Cock's Kidney

Manganese is essential trace element for organisms, which plays an important role in growth, development and breeding. Simultaneously, it is also a common environmental pollutants. The excessive of manganese can cause manganis and disturb the nervous, respiratory, genitourinary ,immune, and cardiovascular systems. Recently the researches of manganism mainly focus on human and mouse,but rarely on poultry. In the study, The 240 healthy Hyline cocks of 50 days were used to be fed a diet normal, low, moderate and high dose of Manganese chloride and each divided into 60. Normal group fed basic diet, low-dose group fed basic diet per kilogram add 500mg MnCl2, moderate and high-dose group fed basic diet per kilogram and add 800 mg MnCl2 and 1 700 mg MnCl2 respectively.To kill 30 d, 60 d and 90 d cocks for sampling, and observe postmortem, microstructure and ultrastructure of nephridial tissue ,contests of Mn, Fe, Ca, Cu, Zn in kidney, antioxidant tests in serum and kidney, tests of NO metabolism and kidney function, contests of carbonyl in kidney and protein-DNA crosslinking (DPC), detection of apoptosis and expression of Fas, Caspase-3 mRNA in kidney according to Real-time Quantitative PCR, in order to assess the effect of manganism on kidney function of cock and clarify preliminary toxicity mechanism of manganism to kidney. The results showed as follows:1. According to postmortem, microstructure and tests in serum and kidney, which is proved that manganis can cause the injury in cock kidney and reduce the physiological function.2. Manganese accumulated in kidney of cock undergoing manganism with incremental contest of coppor and decreasing content of iron and zinc, through detecting contests of Mn, Fe, Ca, Cu, Zn in kidney, but changes in calcium content of the basic upward trend3. Chicken manganese can induced oxidative stress in kidney tissue, caused activities of CAT and SOD fell, DPC, MDA, and protein carbonyl content increased, and the impact on NO content and NOS activity, thus changing the system of enzymes and non-enzymatic antioxidant capacity.It maked the body oxidation and antioxidant balance changes, which resulted oxidative damage and apoptosis.4. The detection of expression of Fas, Caspase-3 mRNA in kidney showed Fas,Caspase-3 mRNA from toxicity group were higher than normal group, which revealed that Mn could induce apoptosis through rising of expression of Fas, Caspase-3 mRNA.This paper summarized the oxidative damage, free radical metabolism, kidney function, and expression of Fas, Caspase-3, which further revealed toxicity mechanism of manganism to kidney.