Kohno Y, Ohta K, Suwa T, Suga T
Research Center, Taisho Pharmaceutical Co., Ltd., Ohmiya, Japan.
Antimicrob Agents Chemother. 1990 Apr;34(4):562-7. doi: 10.1128/AAC.34.4.562.
The antimicrobial activity of clarithromycin was compared with that of erythromycin in experimentally infected mice by whole-body autobacteriography. In mice with systemic staphylococcal infections, the number of vital microbes in the body was relatively low in the early period after oral administration of erythromycin, but increased thereafter to the levels found in nonmedicated control mice. On the other hand, with clarithromycin treatment, a significantly smaller number of microbes was evident throughout the body. The microbes were scarcely seen in the parenchyma of any organs during the examination period. This potent antimicrobial activity of clarithromycin compared with that of erythromycin was further demonstrated in mice with respiratory infections. On the other hand, to examine the distribution properties of both antibiotics in the whole body, an autoradiographic study was carried out with [N-methyl-14C]clarithromycin and [N-methyl-14C]erythromycin. Both labeled antibiotics were distributed widely throughout the body after oral administration in both uninfected control mice and mice with systemic infections. However, the radioactivity was more marked and persistent for [14C]clarithromycin than it was for [14C]erythromycin, particularly in the lungs. The observations described above indicate the superior in vivo antimicrobial activity of clarithromycin compared with that of erythromycin and suggest that the superiority of clarithromycin is largely attributed to its favorable distribution properties. The advantages of whole-body autobacteriography, coupled with whole-body autoradiography, are discussed.
通过全身自显影术，比较了克拉霉素与红霉素在实验性感染小鼠体内的抗菌活性。在患有全身性葡萄球菌感染的小鼠中，口服红霉素后早期体内存活微生物数量相对较低，但此后增加到未用药对照小鼠的水平。另一方面，用克拉霉素治疗时，全身可见的微生物数量明显较少。在检查期间，任何器官的实质中几乎都看不到微生物。在患有呼吸道感染的小鼠中，进一步证明了克拉霉素与红霉素相比具有更强的抗菌活性。另一方面，为了研究两种抗生素在全身的分布特性，用[甲基-14C]克拉霉素和[甲基-14C]红霉素进行了放射自显影研究。在未感染的对照小鼠和患有全身性感染的小鼠中，口服给药后两种标记抗生素均广泛分布于全身。然而，[14C]克拉霉素的放射性比[14C]红霉素更明显且持续时间更长，尤其是在肺部。上述观察结果表明，克拉霉素在体内的抗菌活性优于红霉素，并表明克拉霉素的优势很大程度上归因于其良好的分布特性。讨论了全身自显影术与全身放射自显影术相结合的优点。
