Jurilj N, Pfeifer U
Department of Biology, Stomatological Faculty, University of Zagreb, Yugoslavia.
Virchows Arch B Cell Pathol Incl Mol Pathol. 1990;59(1):32-7. doi: 10.1007/BF02899384.
Cytoplasmic growth (hypertrophy) presupposes a positive metabolic balance brought about by increased anabolic and/or decreased catabolic processes. Degradation of cytoplasmic components takes place in autophagic vacuoles (AVs) whose volume fraction may be taken as a measure of the relative rate of degradation of cytoplasmic components. Male adult Sprague-Dawley rats (n = 80) were unilaterally nephrectomized (n = 40) or sham-operated (n = 40) and were killed 3.5-57.5 h p.o. The volume density of AVs in parenchymal cells of renal cortical convoluted tubules was determined morphometrically by systematic evaluation of large test fields in the electron microscope. During compensatory renal growth, the volume densities of autophagic vacuoles were reduced at day 0 (3.5-8 h p.o.), day 1 (20.5-33.5 h p.o.) and day 2 (44.5-57.5 h p.o.) by 49% (p less than 0.01), 43% (p less than 0.05), and 19% (n.s.), respectively, when compared with sham-operated controls. No decrease, and even an increase, in the AV-volume fraction was found in liver parenchymal cells of the unilaterally nephrectomized animals. This indicates that inhibition of autophagy is not a general response after unilateral nephrectomy, but is confined to the growing kidney, where it may represent a significant factor in the increase of cytoplasmic mass.
细胞质生长（肥大）以合成代谢增加和/或分解代谢减少所带来的正代谢平衡为前提。细胞质成分的降解发生在自噬泡（AVs）中，自噬泡的体积分数可作为细胞质成分相对降解速率的一个衡量指标。成年雄性Sprague-Dawley大鼠（n = 80），其中40只接受单侧肾切除手术，40只接受假手术，术后3.5 - 57.5小时处死。通过电子显微镜下对大视野的系统评估，形态计量学测定肾皮质曲管实质细胞中自噬泡的体积密度。在肾代偿性生长过程中，与假手术对照组相比，在术后第0天（3.5 - 8小时）、第1天（20.5 - 33.5小时）和第2天（44.5 - 57.5小时），自噬泡的体积密度分别降低了49%（p < 0.01）、43%（p < 0.05）和19%（无统计学意义）。在单侧肾切除动物的肝实质细胞中未发现自噬泡体积分数降低，甚至有所增加。这表明自噬的抑制并非单侧肾切除后的普遍反应，而是局限于生长中的肾脏，在那里它可能是细胞质质量增加的一个重要因素。
