[Ultrastructural characteristics of the tubular histion in the system of nephron protein reabsorption in massive proteinuria].

18 puncture renal biopsies obtained from children aged 6-12 years with primary nephrotic syndrome were studied using electron microscopic to examine the components of tubular histion in the system of nephron protein reabsorption in massive proteinuria. The results indicate changes in the interstitial connective tissue associated with collagen formation. The endothelium of peritubular capillaries demonstrated both adaptive and destructive. One of the manifestations of adaptive reactions was an additional pinocytotic vesicular mechanism of protein transport through the endothelium, described in this paper. Fenestrations are regarded as specialized cellular structures which may be formed in different cytoplasmic areas. Evidence is presented to substantiate the cascade pattern in the development of changes in the proximal tubule epithelium-interstitial connective tissue-capillary endothelium system.