A study on cardiac injury of methamphetamine abusers

研究长期给予甲氧苯丙胺（MA）对动物的影响。MA 5. 10. 20 mg/kg B.W.注射给ddy雄性小鼠，每周6次，持续2或4周。在显微镜观察中发现：肥大。萎缩嗜酸性改变、空泡化、收缩带坏死和肌纤维排列紊乱。最小片状纤维化。间质水肿和小圆细胞浸润。病变主要见于左心室和室间隔，但三角区的肌纤维排列紊乱较为突出。电镜下见肌节膜进一步不规则，肌节过度收缩，条索增厚。肌原纤维成分和线粒体增加，肌浆网扩张。肌原纤维消失。有时可见线粒体变性和肌原纤维排列紊乱。此外。肌膜上有时可见许多单膜小泡。塞塞德河畔 ...更多信息 面囊大小与扩张的肌浆网相似，有时与肌膜融合，可见于基底膜内。在内皮细胞和毛细血管腔内。一般而言，这些心脏病变的严重程度与MA给药的剂量和持续时间成比例。而小剂量MA组肌纤维排列紊乱较多。然后，我们比较了MA后的病变与儿茶酚胺给药。并观察了β-受体阻滞剂和钙拮抗剂的作用。去甲肾上腺素给药后的心脏病变与MA给药后相似，但程度有限。恰恰相反。术前应用普萘洛尔和维拉帕米可预防心脏病变的出现。心肌肌球蛋白的焦磷酸盐凝胶电泳分离模式与对照组有显著差异。因此。在MA滥用者中发现的各种心脏病变似乎可以用MA本身的心脏毒性来解释。更进一步。我们的结果表明。MA通过神经末梢释放的儿茶酚胺诱导心脏损伤。可能还涉及到大量caleium。少

To investigate the effects of long-term mechamphetaminc(MA) administration in animals. MA 5. 10. 20 mg/kg b.w. was injected to ddy male mice 6 times per week for 2 or 4 weeks. In microscopic observations there were the findings: hypertrophy. atrophy. eosinophilic changes, vacuolation contraction band nccrosis and disarray of myofibers. minimum patchy fibrosis. interstitial edema and infiltrations of small round cells. These lesions were mainly seen at the left ventricle and the septum except disarray of myotibers which was prominent at the triangle region. Electorn microscopy revealed further appearance of irregularity of sarcolomma, hypercontraction of sarcomere, thickning of % band. increase in myofibrillar elements and mitochondria and dilatation of the sarcomplasmic reticuliums. Dissapearance of myofibrils. degenerations of mitochondia and myofibrillar disarray were sometimes seen. Furthermore. many single membrane vesicles were sometimes observed bancath the sarcolemma. Thesed sur … More face vesiclees were similar to dilated sarcoplasmic reticulums in size, sometimes fused with sarcolomma and seen in the basement membrane. inthe cndothelial cells and in the capillary lumen. In general, the severity of these cardiac lesions were in proportion to both the doso and the duration of MA administrated. but disarray of myofibers were rather found frequently in the group administered smaller dose of MA. We then compared the lesions by MA with those after administration of catecholamine. and also examined the effect of -blocker and Ca-antagonist. The cardiac lesions after norepincphrine administration were similar to those after MA administration but to a limited extent. On the contrally. premedication of propranolol and verapamil prevented the appcarance of the cardiac lesion. isolorm pattern of cardiac myosin of the mice administered MA as by pyrophosphate gei cicotrophoresis showed to so remarkable difference from that of controll mice. Thus. various cardiac lesions found in MA abusers seemed to be explained by the cardiac toxicity of MA by itself. Furtheermore. our result suggests that. MA induces cardiac injury through catecholamine released from nerve endings. and possibly caleium everioad may be also involved. Less