Smaoui H, Schaeverbeke M, Mallié J P, Schaeverbeke J
Laboratoire de Biologie Cellulaire, Université Paris 7, France.
Pediatr Nephrol. 1994 Aug;8(4):447-50. doi: 10.1007/BF00856528.
Changes in kidney maturation in utero have been reported after gentamicin administration to pregnant rats. While the proteinuria commonly observed could be related to modifications of the glomerular basement membrane, perturbed renal protein handling could be accounted for by changes in the proximal tubular cells. Therefore, we studied the effect of gentamicin on the renal handling and transport of proteins in proximal tubular cells using the horseradish peroxidase, a fluid-phase marker, as a probe. Gentamicin was administered intraperitoneally to pregnant Wistar rats (75 mg/kg body weight per day) and neonatal kidneys were studied 1 day after birth. In proximal tubular cells of the deep cortical area, containing the fully matured nephrons of neonates, the transport and digestion of reabsorbed peroxidase was considerably reduced compared with controls where peroxidase reached lysosomes after endocytosis. Urinary protein excretion increased in treated animals. We conclude that gentamicin, entering the proximal tubular cells via the endocytic pathway, decreases the tubular reabsorption of proteins, thus increasing urinary protein excretion.
据报道，给怀孕大鼠注射庆大霉素后，子宫内肾脏成熟过程会发生变化。虽然常见的蛋白尿可能与肾小球基底膜的改变有关，但近端肾小管细胞的变化可能是导致肾脏蛋白质处理紊乱的原因。因此，我们使用辣根过氧化物酶（一种液相标记物）作为探针，研究了庆大霉素对近端肾小管细胞中蛋白质的肾脏处理和转运的影响。给怀孕的Wistar大鼠腹腔注射庆大霉素（每天75mg/kg体重），并在出生后1天研究新生大鼠的肾脏。在深层皮质区域的近端肾小管细胞中，这些细胞包含新生儿完全成熟的肾单位，与对照组相比，重吸收的过氧化物酶的转运和消化显著减少，在对照组中，过氧化物酶通过内吞作用到达溶酶体。治疗组动物的尿蛋白排泄增加。我们得出结论，庆大霉素通过内吞途径进入近端肾小管细胞，减少了肾小管对蛋白质的重吸收，从而增加了尿蛋白排泄。
