[Effect of oxymatrine on prolonging the survival time of cardiac tissue allograft in mice and its immunologic mechanisms].

Oxymatrine is an extract from Sophora flavescens Ait. A daily dose of 75 mg/kg or 225 mg/kg of oxymatrine was given to the recipient intramuscularly for 14 days. The survival time of cardiac tissue allograft was prolonged significantly to 12.2 days (at the dose of 75 mg/kg, P less than 0.05) and 15.7 days (at the dose of 225 mg/kg, P less than 0.001) by oxymatrine, while that in the control group was 10.8 days. The effects of oxymatrine on immune-function in BABL/c mice with or without heart allograft were further studied. Experiments showed that in vitro spontaneous proliferation of spleen cells increased markedly on the 10th day after transplantation, while the proliferation response to Con A of spleen cells decreased. The spontaneous proliferation and proliferation responses to Con A or to LPS of spleen cells could be inhibited significantly in normal mice by oxymatrine. The proliferation response to LPS of spleen cells and RPFC was inhibited obviously in transplanted mice by oxymatrine. However, oxymatrine did not affect the proliferation response to Con A of spleen cells, which had been decreased after transplantation. The results suggested that this drug exhibited selective immuno-suppression on function of B cells without obvious effect on T cell function in transplanted mice. This characteristics of the drug seemed beneficial for avoiding side-effect produced by the conventional immuno-suppressive agents.