The apoptosis and the expression of p53, bcl-2 and Bax in myocytes of chronic rapid ventricular pacing-induced congestive heart failure (CHF) in rabbits were investigated. The CHF rabbit model (P,n=7) was established by chronic rapid ventricular pacing for 3 weeks. By using TUNEL technique the apoptosis in the myocytes in the rabbit model was studied and the expression of p53, bcl-2 and Bax in myocytes was detected by using immunohistochemical method. Sham-operated (C,n = 9) group served as control group. The results showed that there were about 4033±884. 56 apoptotic cells/10⁶ myocytes in P group, but no apoptotic cells were found in C group. Myocytes positive for p53 immunoreactivity (18.86±8.48 vs 5.06±0.87,P<0.01) and positive for Bax immunoreactivity (7. 15±1. 91 vs 0. 43±0. 09,P<0.01) were increased in P group as compared with those in C group, while the myocytes positive for bcl-2 immunoreactivity (7. 08±1.05 vs 14. 97±4.47,P< 0.01) and the ratio of bcl-2/Bax were decreased in P group as compared with those in C group. Apoptosis was involved in the development of CHF induced by continuously rapid ventricular pacing in rabbit. The expression of p53 and Bax was increased, while the expression of bcl-2 was inhibited. These might play an important role in the acceleration of the apoptosis.

The effect of Ligustrazine on the hematopoiesis after bone marrow transplantation (BMT) in allogenic BMT mice was investigated. After the typical mice model of allogenic BMT had been established, the mice were randomly divided into three groups: BMT group, Ligustrazine group and normal group. The BMT group was given normal saline (0. 2 ml, twice a day) through gastric tube, while the Ligustrazine group was given Ligustrazine through gastric tube (0. 2 ml, twice a day). At the 1st, 7th and 14th day after BMT, we observed the peripheral blood cells and bone marrow nuclear cells (BMNC), as well as the expression level of Heparan Sulfate (HS) and stromal cell derived factor-1 (SDF-1) on bone marrow sections by using immunohistochemistry (SABC-AP), the expression of CXCR4 on the BMNC. The results showed that on the 7th and 14th day, the peripheral blood white cells, platelets, BMNC and the expression levels of CXCR4, HS and SDF-1 were significantly higher in Ligustrazine group than in the BMT group (P<0. 05). It was concluded that Ligustrazine could promote hematopoiesis at the early stage of hematopoietic reconstitution after BMT.