链霉素对于神经结构的毒害

NEUROTOXICITY OF STREPTOMYCIN(RÉSUMÉ)

十三个成长的豚鼠分为三粗,2个作正常对照,此外6个和5个每日分别注射链霉秦硫酸盐,一公斤体重200和400毫克,共经21至60天。未了,豚鼠都经过平衡和听觉的测验。各脑分别染制Nissl和Bielschowsky切片。显微镜的检查得到以下的结果。神经系中普见血管的病变。血管塌陷,管外间质水肿。邻近的神经组织失血软化。神经纤维表现髓鞘溶解。中毒的神经细胞脱水萎缩,常见胞核偏位,染色质偏聚、结块。也时有神经胶质增生和神经吞噬现象。二组豚鼠在位听神经的前庭系和耳蜗系都有中毒的征象。在周缘部和中枢部,前庭系各极结构的病变,与耳蜗系相较,更为严重。在注射轻剂和重剂的二组豚鼠,神经系中毒的部位和性质是相似的,但重剂组的病变程度较高。在位听系,中毒的病变同时见于周缘部和中枢部。中毒的第一性的问题——在周缘,抑在中枢——是不存在的。周缘和中枢各有一系结构,病变的表现不沿神经传导的路线;病变的轻重也不随路线上地位的高低。周缘和中枢的各项结构是各自中毒的。链霉素不仅毒害位听神经一系,而更损伤其它感觉系(如三叉神经系)和运动系——特是内脏运动系——的结构。链霉素中毒是一般性的,但有些结构特易感受它的毒害。在各级结构中,神经细胞的化学合成决定它们反应链霉素的灵钝和轻重。链霉素伤害高级的脑部,这多属运动性,特是内脏运动性。间脑的内脏性核团、纹状体簇和内脏性皮质中毒特别剧烈。链霉素中毒症状广泛,这是有神经基础的。链霉素的毒质伤害全神经系,也影响全身;为医疗使用这个抗菌素,关于患者对此药的敏感,剂量和疗程是要慎重考虑的。

Thirteen adult guinea-pigs were divided into 3 groups:2 as normal controls;6 and 5 being treated with streptomycin sulphate 200 and 400mg per kilo body weight res-pectively for 21—60 days.The vestibular and auditory functions were tested.Their brains were prepared for Bielschowsky and Nissl sections.Microscopic examination re-vealed the following facts.Vascular disturbances prevail in the nervous system.The blood vessels are crumpled with concommittent perivascular edema.The adjacent nervous tissue shows ischemic softening and the nerve fibres become demyelinated.The intoxicated nerve cells are generally dehydrated and shrunken often with eccen-tricity of nuclei and chromophilic lumps.Gliosis and neurophagosis are common.The vestibular and cochlear systems of the eighth or stato-acoustic nerve exhibit intoxicative changes in the 2 groups of animals.On the peripheral as well as the central side,the degeneration of the vestibular structures supercedes that of the cochlear system.The site and nature of the intoxication are much alike in the light and heavy-dose groups,yet the latter shows a higher severity.The degenerative alterations appear simultaneously in the perpheral and central struc-tures.A question of primacy in intoxication—peripheral or central—is not existent.There is a chain of structures on the peripheral and central sides of the stato-acoustic system;their degeneration does not proceed along the conduction path,nor the degree of intoxication varies with their relative positions on the conduction scale.The peri-pheral and central units get intoxicated independently.Besides the stato-acoustic structures streptomycin afflicts other sensory(e.g.trige-minal)and motor systems,the viscero-motor in particular.Streptomycin intoxication is general in nature,yet some structures are especially sensitive to it.The relative vulnerability to streptomycin of the nervous structures is apparently conditioned by their chemical constitution.Streptomycin injuries higher brain parts which are mainly motor,especially viscero-motor.The diencephalic viscero-motor nuclei,the striate complex and the visceral cor-tex are excessively disintegrated.The extensive intoxicative manifestations have a neurological basis.The toxin of streptomycin affects the entire nervous system and hence the whole bodily mechanisms.Its medical application calls for a meticulous consideration with respect to the patient’s sensitivity to the antibiotic,the size of the dose and the length of the therapeutic course.