Action of NO and TNF-alpha release of rats with cadmium loading in malfunctiion of multiple system organ.

Thirty-six healthy Sprague-Dawley male rats were used and divided randomly into a control group (group C), a medium-dose cadmium loading group (group M) and a high-dose cadmium loading group (group H). Cadmium chloride was diluted with saline to contain 0.4 mg/ml of autoclaved cadmium solution. Groups M and H were injected in the abdominal cavity with 0.5 and 1.0 mg of cadmium per kg body weight respectively, and group C with saline of the same dosage as in group H over 7 d. Six rats of each group were killed on the 4th day and 7th day after cadmium loading, respectively, and blood, testis, liver and heart were collected. Cadmium content, changes in nitric oxide and tumor necrosis factor-alpha were studied in blood and the tissues of testis, liver and heart. Results showed that during the entire experimental period, body weight in groups M and H decreased significantly as compared with that in group C; cadmium concentration increased significantly in testis, heart and liver of groups M and H, and rose with increased dosage and time of cadmium loading; there was no obvious difference in plasma nitric oxide between groups M and C, though nitric oxide was higher in group M than in group C. Nitric oxide in group H was significantly superior to that in group C. Plasma tumor necrosis factor-alpha was markedly higher in groups M and H than in group C. Nitric oxide contents in the rat s testis, liver and heart homogenates with cadmium loading were higher than those in group C or significantly superior to group C. The same changes in tumor necrosis factor-alpha in the tissue homogenates of the testis and heart were found, but no obvious difference in tumor necrosis factor-alpha in the liver between the three groups was observed. It is suggested that the massive release of nitric oxide and tumor necrosis factor-alpha induced by cadmium loading may play an important role in the induction of malfunction of multiple systems or organs in rats.