活体冷冻技术联合心电图研究小鼠心脏微循环

The use of in vivo cryotechnique in combination with electrocardiograph to study cardiac microcir- culation in living mouse

目的应用活体冷冻技术（IVCT）联合心电图研究不同血流动力学条件下活体小鼠心脏微循环变化。方法分别在正常血流、心肌缺血和心脏骤停等血流动力学条件下，心电图监测的同时行小鼠心脏活体冷冻。连续的石蜡切片后，分别进行苏木精-伊红（HE）染色、过碘酸-希夫氏染色和血清白蛋白、免疫球蛋白荧光染色及共聚焦显微镜分析，并进行统计分析。结果与正常血流动力学相比，心肌缺血时，微血管内红细胞数量减少和形态改变、心肌细胞糖原缺失、血清白蛋白异位分布到心肌细胞浆内、T小管网络破坏、间距增宽；心脏骤停条件下，红细胞数量形态各异、心肌细胞糖原缺失、T小管网络破坏、间距变窄。结论应用活体冷冻技术与心电图即刻捕获了不同血流动力学条件下心肌细胞微循环及微环境的组织病理学改变。

Objective The use of in vivo cryotechnique （IVCT） in combination with electrocardiograph （ECG） to study cardiac microcirculation under different hemodynamic conditions in living mouse. Methods Living mouse heart monitored by electrocardiograph was suffered from IVCT and freezing substitution under normal blood flow, myocardial ischemia or cardiac arrest conditions. Hematoxylin eosin （HE） staining, Schiff＇s staining and immunofluorescence staining for serum albumin, immunoglobulin were utilized on continuous paraffin sections, respectively. Confocal microscopy and statistical analyses were used. Results Comparing with normal hemodynamics, microvascular red cell volume reduction, morphology changed, myocardial cell glycogen loss, serum albumin ectopic distribution to myocardial cytoplasm, T tubular network failure and spacing width were happened in myocardial ischemia condition; different shapes of red blood cells, myocardial cells glycogen deficiency, T tubular network failure and interval narrowing were found under cardiac arrest conditions. Conclusions Cardiac microcirculation, pathological changes of myocyte and its surrounding mieroenvironment in living mouse heart can be immediately captured in situ by the application of IVCT and ECG.