Nonclercq D, Toubeau G, Laurent G, Schaudies R P, Zanen J, Heuson-Stiennon J A
Service d'Histologie, Faculté de Médecine, Université de Mons-Hainaut, Mons, Belgium.
Eur J Morphol. 1993 Mar-Jun;31(1-2):65-71.
The present study was undertaken to analyze, at the cytological level, the intrarenal distribution of epidermal growth factor (EGF) in normal conditions and after drug-induced tubular injury. Female Sprague-Dawley rats were injected with gentamicin (50 mg/kg.day) for 4 days to induce tubular necrosis and were terminated 4 days after the last drug administration. For light microscopy, EGF immunoreactivity was demonstrated by immunogold-silver staining. In the kidneys of control rats EGF was found associated with distal tubules (cortex and outer medulla). Kidney exposure to gentamicin resulted in a drastic decrease of EGF immunoreactivity. For the electron microscopy study, immunoreactive EGF was detected on ultrathin sections by immunogold labeling. Within distal tubules epithelium of control animals, immunoreactive material was predominantly seen on the basolateral membrane, and to a much lesser extent in the cytoplasm or on the apical membrane. After treatment with gentamicin, there was a reduction of the density of gold particles observed in distal tubule cells. Interestingly, gold particles also appeared, but at a lower density, in proximal tubule cells. In these cells, EGF immunoreactivity also seemed membrane-bound and was mostly observed on (or next to) the basolateral membrane.
本研究旨在从细胞学水平分析正常情况下及药物诱导肾小管损伤后表皮生长因子（EGF）在肾内的分布。将雌性Sprague-Dawley大鼠注射庆大霉素（50mg/kg·天），持续4天以诱导肾小管坏死，并在末次给药后4天处死。对于光学显微镜检查，通过免疫金银染色显示EGF免疫反应性。在对照大鼠的肾脏中，发现EGF与远端小管（皮质和外髓质）相关。肾脏暴露于庆大霉素导致EGF免疫反应性急剧下降。对于电子显微镜研究，通过免疫金标记在超薄切片上检测免疫反应性EGF。在对照动物的远端小管上皮内，免疫反应性物质主要见于基底外侧膜，在细胞质或顶端膜上的程度要小得多。用庆大霉素治疗后，在远端小管细胞中观察到金颗粒密度降低。有趣的是，在近端小管细胞中也出现了金颗粒，但密度较低。在这些细胞中，EGF免疫反应性似乎也与膜结合，并且大多在基底外侧膜上（或旁边）观察到。
