摘要
大剂量内毒素（ＬＰＳ）可引起成年雄性小鼠胸腺严重萎缩，胸腺细胞大量凋亡。但对ＬＰＳ耐受动物的胸腺重量、胸腺指数、胸腺细胞总数及活细胞数均明显高于非耐受组，且胸腺细胞ＤＮＡ断裂少，电泳未见凋亡细胞特有的“梯状”ＤＮＡ碎片出现。表明耐受内毒大的动物其胸腺细胞凋亡亦呈现耐受性。
hymocyte apoptosis was investigated in endotoxin(LPS)tolerant mice induced by in-traperitoneal injection of lethal dose of LPS 24h after administration of sublethal dose of LPS(500μg·kg-1 for consecutive 2 days)and lethal dose of LPS injection as control. Thymuses fromboth groups were procured and assessed for changes in thymus weight (TW,mg), thymus index(TI, TW.g-1 body weight),total thymocyte mumber,thymic viable cell yield,percentages ofDNA fragmentation determined by the diphenylamine method and by evidence of ladder of nucleo-somal DNA fragments by agarose gel electrophoresis 24h after administration of lethal doses ofLPS. Severe thymus atrophy and accelerated thymocyte apoptosis were observed in nontolerantmice in a dose-dependent manner. But the survival rate,TW,TI,total and viable thymocyte num-ber in nontolerant mice were significantly lower than those in tolerant animals. It is very interest-ing that not only was percentage of DNA fagmentation in thymocyte from tolerant mice markedlylower than that from nontolerant mice, but also the apoptotic ladder of DNA was almost unde-tected in thymocyte from tolerant animals when the doses of LPS ranged from 5mg·kg- 1 to 20mg·kg-1 body weight. These indicate that endotoxin tolerance can protect thymocytes againstapoptosis induced by lethal dose of LPS in vivo.
出处
《湖南医科大学学报》
CSCD
1996年第3期187-191,共5页
Bulletin of Hunan Medical University
