Effect Of Cadmium On Synovium And Cartilage In Rabbits Chronicly Cadmium Poisoned By Drinking Water

Objective:1 To study the effect of cadmium chloride on cartilage, synovium and general growth in rabbits chronicly cadmium poisoned by drinking water.2 In order to provide some theoretical basis for further research on the effect of cadmium on synovium and cartilage in humans and for quicker control of heavy mental pollution.Methods:Take forty New Zealand white rabbits of two and a half months old.They were randomly divided into two groups,one experimental group,the other as control group, male and female is half, single cage feeding. The control group was feeded with normal drinking water, the experimental group was feeded with 5mmol/L cadmium chloride water.Their body weight was measured at the beginning of the experiment and in the end also. These rabbits were sacrificed after 3 months later, the content of cadmium in blood was measured.The measured items of synovium including the content of cadmium, pathological inflammation grade analysis and RT-PCR measuring the expression level of IL-1β, TNF-αmRNA. The measured items of cartilage including the content of cadmium,histological observation through optical microscope, histological scoring according to the method of Mankin, RT-PCR measuring the mRNA expression level of typeⅡcollagen, glycosaminoglycan, metalloproteinases-13(MMP-13), tissue inhibitor soft matrix metalloproteinase's-1 (TIMP-1),interleukin-1beta (1IL-1β),and tumor necrosis factor-a (TNF-a).Examine the changes in morphology of articular cartilage in terms of mitochondria, rough endoplasmic reticulum, the other organelles and extracellular matrix of collagen fibers by electron microscopy.Results:Chronic cadmium -poisoned drinking water seriously affects the growth of rabbits. Cadmium can accumulate in rabbit's articular cartilage and synovial membrane with the cadmium -prolonged intervention.There were differences in the Markin score between two groups,and no differences were found about synovium in pathological inflammation grade analysis. RT-PCR measuring the expression level of chondrocyte type II collagen, matrix metalloproteinase-13(MMP-13),tissue inhibitor of metalloproteinase-1 (TIMP-1), interleukin-1β(1IL-1β), and tumor necrosis factor-a (TNF-a) mRNA showed that the mRNA expression of the type II collagen, glycosaminoglycan, matrix metalloproteinase-13 (MMP-13) was significantly increased in the experimental group. (P<0.05),Statistically significant.No significant difference was found in the mRNA expression of tissue inhibitor of metalloproteinase -1 (TIMP-1) in terms of the experimental and control groups. (P> 0.05),not Statistically significant. The mRNA of interleukin-1β(1IL-1β) and tumor necrosis factor-α(TNF-α) was not expressed in the cartilage. It has been expressed in the synovial membrane, but no significant difference was showed in the experimental and control groups. (P>0.05),not Statistically significant. Abnormalities of chondrocyte were dramatically clear in electron microscopy of the experimental group.Conclusion:Chronic cadmium- poisoned drinking water can greatly affect the growth and development of rabbit, It can result in the accumulation of cadmium in the articular cartilage and synovial membrane of rabbit.It also probably can make osteoarthritis happen.