Abstract:

 Our research was conducted to observe the effect of metallothionein (MT) on cow heat stress splenic lymphocytes apoptosis, and study MT on the regulation of the thermo-oxidative stress-induced apoptosis/necrosis and mitochondrial membrane potential (ΔΨm). The splenic lymphocytes apoptosis phenomena were observed by using fluorescence microscope. The apoptosis and necrosis rates were assayed for adopting Annexin V-FITC with flow cytometer. The ΔΨm of cells was assayed with flow cytometer through loading JC-1. Results were as follows: MT only has inhibitory effect on the apoptosis induced by heat stress, and when MT was 5.25-8.25 μg·mL^－1, the apoptosis can be promoted lowly. The necrocytosis can also be promoted lowly by the lower MT when the concentration was 2.25 μg·mL^－1. And the ΔΨm value can be increased more by MT, but the high stress of cell require higher concentration of MT, and the normal cell require moderate concentration (3.75-6.75 μg·mL^－1), cell can not be protected enough by the other concentration. These findings indicate that the 1 hour culture in 43℃ of cow spleen lymphocytes can improve mitochondrial membrane potential, as well as the necrosis rate. Nevertheless, mitochondrial membrane voltage can be improved, and necrosis caused by heat stress could be restrained because of adding MT in cell culture medium. Therefore, It has more practical meaning for adopting adding MT to improve the integrity of cellular mitochondria than high fever, at the same time, it also shows that the mitochondrial pathway is one of signal transduction pathway which MT regulating apoptosis/necrosis.