To study the effect and mechanism of snake venom ofAgkistrodon Halys Pallas in Zhejiang in inducing human leukemic Jurkat cell apoptosis. IC50 and growth curve of Jurkat cells were detected by MTT; percentage of apoptotic cells was analyzed by flow cytometry (FCM) using Annexin V FITC/PI staining method; cell cycle was also detected by FCM and protein expression of Bcl-2 gene was detected by FCM and Western-blot. Zhejiang viper venom could inhibit the growth of Jurkat cells dose-dependently

induce the cell apoptosis

with the bcl-2 protein expression down-regulated. The strongest effect was shown at 48 hrs

it weakened gradually

and the Jurkat cells restored slowly in low concentration of snake venom. Zhejiang viper venom could induce apoptosis of human leukemic Jurkat cell in dose-dependent manner

the effect is related to the down-regulation of Bcl-2 protein expression.