中华眼镜蛇心脏毒素和磷脂酶A2引起小白鼠骨骼肌损伤的超微结构研究

ULTRASTRUCTURAL STUDY ON MYONECROSIS OF MICE SKELETAL MUSCLE INDUCED BY THE CARDIOTOXINS AND PHOSPHOLIPASE A2 FROM NAJA NAJA ATRA VENOM

中华眼镜蛇(Naja naja atra)的三个单一组份:心脏毒素Ⅰ、心脏毒素Ⅱ和磷脂酶A(称简为CTⅠ,CIⅡ和PhA),两个混和组份:CTⅠ-PhA和CTⅡ-PhA,分别注射到小白鼠后肢小腿胫骨前肌内,观察和研究小白鼠骨骼肌损伤的超微结构变化。这三个毒性组份均能造成小白鼠骨骼肌肌纤维的明显损伤和坏死,肌质膜、核膜和线粒体膜损伤,肌丝溶解而形成各种絮状游离坏死小块;肌小管系统消失;线粒体肿胀并形成含有嵴碎片的空泡;肌质网溶解;肌纤维内出现有大量囊泡状结构物。整个肌纤维变成一种含有各种细胞器残骸并由破损肌质膜所包围的低电子密度破损细胞。五个组份所形成的超微结构损伤变化并无显著差异,CTⅠ-PhA或CTⅡ-PhA这两个混合组份比相应的单一组份的损伤似乎更严重些。

Three simple components of Naja naja atra venom:cardiotoxin I(CTⅠ),cardiotoxin(CTⅡ)and phospholipase A2(PhA2),and their two mixed components:CTⅠ-PhA2 and CTⅡ-PhA2 were injected into the anterior tibial muscle of hind leg of mice.The ultrastructural changes of myonecrosis were observed.All these five fractions caused explicit damage and necrobiosis:the skeletal muscle fibers,sarcoplasmic,nuclear and mitochondrion membranes were broken and dissolved,myofilaments dissolved and transformed into isolated necrotic picces with various shapes,sarcrotubular system disappeared,mitochondrion swelled and vacuolatcd,sarcoplasmic reticulum dissolved,considerable members of bladder-like structures appeared in myoneme.The integrity of myoneme became some less electron-density masses containing a few cellular rcmnents enclosed by a vestige of the myoplasmic membrane.There were no considerable differences of ultrastructural changes induced by these components.It seems that the necrotic effects of two mixed components were more severe than that at three simple components.