Hara T, Harada S, Yamamoto M, Kashitani J, Deguchi T
Jpn J Antibiot. 1983 Nov;36(11):3208-25.
Micronomicin (MCR) is a new aminoglycoside antibiotic produced by Micromonospora sagamiensis var. nonreducans which was isolated from soil collected at Sagamihara City by Nara et al. This antibiotic shows a close similarity to gentamicin C components in physical and chemical properties. The antibacterial activity of MCR is broad-spectrum and almost equal to that of gentamicin C complex. MCR exhibits particularly high activity against Pseudomonas, Proteus, Klebsiella pneumoniae, Serratia, etc. as well as against some Pseudomonas aeruginosa strains resistant to gentamicin C1a. Toxicological studies of MCR in rats were carried out by intravenous injection for safety evaluation. Study on subacute toxicity: Wistar rats were injected intravenously with MCR at the dose levels of 4, 10, 25, 63 mg/kg and 100 mg/kg for 30 days. The results of the studies are as follows: In the subacute toxicity study, animals died at the dose level of 100 mg/kg (10 out of 30 animals). Main changes observed were renal disorders and ataxia which showed a close similarity to those seen in intramuscular toxicity studies in rats. The renal histological disorders occurred mainly at the dose levels of 25 mg/kg and over, but they were slight at the dose levels of 25 mg/kg. Ataxia was observed at the dose levels of 63 mg/kg and over, but its grade was slight at the dose level of 63 mg/kg. The maximum safety dose was equal to in the intramuscular subacute toxicity in rats, 10 mg/kg.
小诺米星（MCR）是由相模小单孢菌无还原变种产生的一种新型氨基糖苷类抗生素，该菌株由奈良等人从相模原市采集的土壤中分离得到。这种抗生素在物理和化学性质上与庆大霉素C组分极为相似。MCR的抗菌活性具有广谱性，几乎与庆大霉素C复合物相当。MCR对假单胞菌、变形杆菌、肺炎克雷伯菌、沙雷氏菌等，以及对庆大霉素C1a耐药的一些铜绿假单胞菌菌株表现出特别高的活性。通过静脉注射对大鼠进行了MCR的毒理学研究以进行安全性评估。亚急性毒性研究：将Wistar大鼠分别以4、10、25、63mg/kg和100mg/kg的剂量静脉注射MCR，持续30天。研究结果如下：在亚急性毒性研究中，100mg/kg剂量组的动物死亡（30只动物中有10只）。观察到的主要变化是肾脏疾病和共济失调，这与大鼠肌肉注射毒性研究中所见的情况极为相似。肾脏组织学病变主要发生在25mg/kg及以上剂量组，但在25mg/kg剂量组时病变较轻。共济失调在63mg/kg及以上剂量组观察到，但在63mg/kg剂量组时其程度较轻。最大安全剂量与大鼠肌肉注射亚急性毒性研究中的相同，为10mg/kg。
