Minguez F, Agra M, Lurueña S, Ramos C, Prieto J
Department of Microbiology, School of Medicine, Complutense University of Madrid, Spain.
Drugs Exp Clin Res. 1990;16(5):231-5.
Isepamicin is a new aminoglycoside drug derived from gentamicin, which is more stable than other aminoglycosides to inactivating enzymes and experimentally is less nephrotoxic than gentamicin or amikacin. In this work a comparative study was carried out on the antibacterial activity (MIC and lethality curves) and the post-antibiotic effect (PAE) of different concentrations of isepamicin, netilmicin and gentamicin on pure cultures of S. aureus and E. coli. The MIC and curves of lethality were determined by conventional methods. The PAE was determined after exposure of the bacterial culture to the antimicrobial one for 1 h at 37 degrees C in a bath with stirring. Elimination of the drug was made by the dilution method. Isepamicin was found to have a MIC four times greater than netilmicin and gentamicin. Its activity over time was similar to that exhibited by other aminoglycosides. At concentrations higher than the MIC, a bactericidal effect was found with the three antibiotics, although isepamicin produced it at lower concentrations. The post-antibiotic effect induced by isepamicin, the same as that of netilmicin and gentamicin, was extensive and depended on the concentration and the strain used. Isepamicin shows antibiotic activity over time and a PAE similar to the other aminoglycosides tested but, unlike them, it has a faster activity, less toxicity and better resistance to inactivating enzymes. For this reason it makes a considerable contribution to antibacterial therapies in severe conditions, including immunodepressed patients who require long-term treatment.
异帕米星是一种从庆大霉素衍生而来的新型氨基糖苷类药物，它比其他氨基糖苷类药物对灭活酶更稳定，且在实验中比庆大霉素或阿米卡星的肾毒性更小。在这项研究中，对不同浓度的异帕米星、奈替米星和庆大霉素对金黄色葡萄球菌和大肠杆菌纯培养物的抗菌活性（MIC和致死率曲线）及抗生素后效应（PAE）进行了比较研究。MIC和致死率曲线通过常规方法测定。将细菌培养物在37℃的搅拌水浴中与抗菌药物接触1小时后测定PAE。药物消除采用稀释法。结果发现异帕米星的MIC比奈替米星和庆大霉素大四倍。其随时间的活性与其他氨基糖苷类药物相似。在高于MIC的浓度下，三种抗生素均有杀菌作用，不过异帕米星在较低浓度时就能产生杀菌作用。异帕米星诱导的抗生素后效应与奈替米星和庆大霉素相同，作用广泛，且取决于所用浓度和菌株。异帕米星随时间显示出抗生素活性，其PAE与其他受试氨基糖苷类药物相似，但与它们不同的是，它活性更快、毒性更小且对灭活酶的抵抗力更强。因此，它对包括需要长期治疗的免疫抑制患者在内的重症抗菌治疗有很大贡献。
