三尖杉酯碱对红系造血机能的影响

用微量甲基纤维素培养方法检测三尖杉酯碱(Harringtonine,Ha)促进小鼠骨髓红系祖细胞CFU-E和BFU-E增殖的作用。结果表明,适当剂量的Ha能增强骨髓红系造血机能;如剂量过大反而起抑制作用。双盲实验也表明Ha有促进骨髓CFU-E和BFU-E增殖的作用。     

Toxic Effects of Dennettia tripetala. Root Extract

Abstract

Toxic effects of the ethyl acetate root extract of Dennettia tripetala. G. Baker (Annonaceae) were studied using in vivo. and in vitro. models. The LD₅₀ of the extract was 1120 mg/kg, i.p. No remarkable change was observed in the major organs on postmortem examination, except for the hyperemia and petechiation of the mucous and serous membranes of gastrointestinal and respiratory tracts. The LC₅₀ of 83.96 ppm and estimated ED₅₀ of 8.4 ppm (95% confidence interval) were obtained following a brine shrimp lethality test. The chronic exposure of mice to the extract showed a significant (p < 0.05) increase in packed cell volume (PCV) and red blood cell (RBC) count. The plant extract (0.5–2.0 g extract/kg feed) also produced a dose- and time-related significant (p < 0.05) reduction in the total white blood cell (WBC) count. The total number of lymphocytes and neutrophils were reduced. There was significant (p < 0.05) decrease in the relative organ weight (ROW) of liver on day 63 for all the treatment groups and spleen for the mice that received 2.0 g extract/kg feed. The extract produced a significant (p < 0.05) increase in ROW of the heart on day 63 in mice fed 2.0 g extract/kg diet. The vascular effects of the extract include degenerative, necrotic, and regenerative changes with cellular (mainly mononuclear leukocytes) infiltration in the portal areas of the liver, which was both dose- and time-dependent. The kidneys showed areas of hyperemia, hemorrhages, tubular epithelial degeneration, and necrosis with mononuclear leukocytes infiltrating the perivascular spaces and interstices.