胆必清颗粒抑制小鼠肠缺血/再灌注所致肝细胞凋亡

目的:研究胆必清颗粒在肠缺血/再灌注组织损伤中对肝细胞凋亡的影响及机理。方法:采用夹闭肠系膜上动脉1小时再灌注2小时的方法建立肠缺血/再灌注损伤模型,TUNEL法观察肝细胞凋亡的情况,荧光法检测肝细胞内钙离子浓度([Ca2+]i),比色法检测肝组织中丙二醛(MDA)及髓过氧化物酶(MPO)水平。结果:与假手术组比较,模型组肝细胞凋亡指数、肝细胞[Ca2+]、iMDA及MPO水平显著增加。与模型组比较,胆必清颗粒显著抑制肝细胞凋亡,降低肝细胞[Ca2+]i、MDA水平及MPO水平。结论:胆必清颗粒具有抑制肠缺血/再灌注损伤引起的肝细胞的凋亡作用。

汉防己甲素对低温灌洗保存大鼠供肝的肝功能影响的实验研究

目的:观察汉防己甲素(TET)在低温灌洗保存供肝时对肝细胞的钙超载及肝功能的影响。方法:低温灌洗保存大鼠肝脏4 h,按保存液的不同分为4组:A组(对照组):乳酸林格液灌洗保存;B组(TET注射组):腹腔内注射TET,乳酸林格液灌洗保存;C组(TET灌洗组):腹腔内注射TET,乳酸林格液中加入TET灌洗保存;D组(Collins组):Collins液灌洗保存,测定供肝低温灌洗保存后肝细胞内钙浓度和肝功能,并在光镜和电镜下观察肝脏的结构。结果:细胞内钙浓度和肝功能测定,各实验组与对照组、C组与B组比较,差异有统计学意义(P<0.05);组织学观察支持以上结果。结论:TET能显著减轻低温灌洗保存下肝细胞的钙超载并起到保护肝功能作用;TET溶液直接灌洗保存供肝比TET腹腔注射效果好;用TET溶液灌洗并保存供肝4 h与Collins液灌洗保存组效果相近;TET对供肝的灌洗保存有积极的作用,因此推断该药有望用于临床供肝的保存。

EGF receptor-mediated intracellular calcium increasein human hepatoma BEL-7404 cells

Epidermal growth factor （EGF） induced intracellular free calcium ([Ca2+]i) response was studied in fura-2- or fluo-3-loaded human hepatoma cells of BEL-7404 cell line. Single cell [Ca2+]i analysis and [Ca2+], measurement in cell populations revealed that EGF triggered a rapid [Ca2+]iincrease in the dose-dependent and time- dependent manner. Pretreatment of cells with an endoplasmic reticulum （ER） Ca2+-ATPase inhibitor, thapsigargin （TG） at 100 nM concentration for 20 min, completely abolished EGF-induced [Ca2+]i increase, and chelating extracellular calcium by excess EGTA partially inhibited the increase.Furthermore, the expression of antisense EGF receptor sequence in BEL-7404 cells suppressed the [Ca2+]i response to EGF. The results suggest that EGF receptor-mediated [Ca2+]i increase in the human hepatoma cells is essentially dependent on the Ca2+ storage in ER.