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Objective: 1. Chronic drinking type of lead poisoning, the lead content and distribution characteristics of the New Zealand rabbit blood, bone, synovium and articular cartilage; 2. Chronic drinking water type of lead poisoning in New Zealand rabbits knee cartilage morphology and articular cartilage composed of ingredients gene expression. Methods: 40 New Zealand white rabbits, male or female, were randomly divided into the experimental group and the control group (n = 20). The control group received normal drinking water breeding; feeding of the experimental group were given drinking water containing lead acetate (1g / L), a total of three feeding, breeding period to observe the animals in each group mental state and weight changes. Randomly selected groups of 14 animals, heart, blood sampling, determination of blood lead levels; take right knee at 1cm femur, Determination of lead content in the bone; take knees synovial determination of the lead content in the synovial membrane; take double knee cartilage, the determination of lead content in the articular cartilage. Randomly selected groups of three animals, cut bilateral complete knee cartilage and synovial general observation morphology, parallel organization decalcified embedded sections, line cartilage HE, safranin O and toluidine blue staining, light microscopy, the line cartilage Mankin histological criteria score line synovial HE staining parallel pathological inflammation grade. Three animals in each group were randomly selected, taking the weight-bearing area of ??the femoral condyle articular cartilage chondrocytes, transmission electron microscopy and its mitochondrial course and distribution of the morphology of the rough endoplasmic reticulum and the extracellular matrix of collagen fibers, modulo articular cartilage mRNA expression levels using real-time quantitative RT-PCR assay for quantification of cartilage type II collagen and glycosaminoglycan. Results: 1 weight gain of the control group, the upward trend; animals of the experimental group compared with the control group it was slow growth, growth curve than straight behind in the control group (P lt; 0.05) to start from the first four weeks of the lead exposure on weight gain, and always maintained at a lower level (P lt; 0.05). 2. Compared with the control group, the experimental group, blood, bone, synovium and articular cartilage in the lead content increased significantly (P lt; 0.01). The lead content in the experimental group the highest bone, followed by the synovial membrane, articular cartilage and blood. The lead content in the articular cartilage showed the lead content in the blood, bone and synovial positive linear correlation (P lt; 0.01). 3 experimental groups articular cartilage, synovial general observation compared with the control group, no significant difference in the articular cartilage surface is smooth and shiny; the synovial no congestion and swelling; HE staining under light microscopy observation showed that the experimental group articular chondrocytes reduced; safranin O and toluidine blue staining, deep stromal staining confirmed lighter than normal cartilage. Cartilage Mankin score and synovitis grading the experimental group than in the control group (P lt; 0.05). Transmission electron microscopy confirmed the irregular shape of the experimental group chondrocytes, membrane border is still clear and discontinuous phenomenon, the cytoplasm mitochondria and endoplasmic reticulum organelle swelling and disintegration seen large vacuoles, nucleus deformation; experimental group sparse compared to the control group of cells around the collagen fibers, no significant grid-like arrangement. The experimental group rabbit knee joint cartilage type II collagen mRNA expression significantly reduced compared with the control group (P lt; 0.05); glycosaminoglycans in articular cartilage mRNA expression significantly reduced compared with the control group (P lt; 0.05). Conclusion: lead poisoning chronic drinking of lead in the blood, bone, synovium and articular cartilage were distributed, the highest of the lead content of bone, synovium, articular cartilage and blood. Articular cartilage lead content in blood, bone and synovial membrane in the lead content of linear positive correlation, lead by inhibiting gene expression in the articular cartilage tissue components, leading to changes in cartilage cell dysfunction and normal articular cartilage structure, thus resulting in the articular cartilage injury.
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