大鼠心肌组织的低温快速冷冻及冷冻置换研究

Researches of Low Temperature Rapid-Freezing and Frozen-Substitution for Rat Heart Muscular Tissues

生物组织的快速冷冻及冷冻置换技术已被用于生物X射线能量色散谱分析的样品制备。快速冷冻能够较好地保持生物组织的结构形态,减少组织移位和组织内元素或离子的丢失、移位、重分布,使生物EDX定量微区分析结果更精确。本文主要探讨了心肌组织及一些细胞器在快速冷冻中的冷冻损伤机理,对心肌组织、细胞间隙、线粒体、细胞核和质膜的冷冻损伤作了较全面的探讨。

Rapid freezing is an ideal method of preparing biological specimens that all conponents are immobilized in a life-like state. This paper discusses in detail ultrastructural changes and freezing damage about rat heart muscle after rapid freezing. Unfixed fresh rat heart muscle were cut to pieces about 100～150μm by microslicer.The pieces were quick- ly injected liquid cryogen Freon 22 by Reichert-Jung Spring-assistant mechanism(KF-80).Frozen specimens were quickly transfered into substitution medium aceton.As stain agent uranyl acetate(20%)were added to sub- stitution medium-acetone.Frozen specimens were kept at —80℃(28h),—60℃(48h),—20℃(12h)and —4℃ (1h). The results showed that the structure of specimens frozen are well and there are no ice crystal in the area to the frozen tissue surface to about 20μm depth.The structure of nucleus,mitochondrion are well.The muscular fiber are regular.However,there are frozen damage and a large number of ice crystals over 20μm depth in the tissue.