Abstract

Laminins are the major water-soluble glycoproteins in the basement membrane of epithelial tissue. The laminin content of the renal parenchyma was studied in rats that were fed a 60-h alternative water diet with either excessive water intake or a complete lack of drinking water. It was shown that osmotic concentration of the urine, which develops due to water deprivation, is accompanied by a quantitative change in the laminin composition. It was found that the level of the laminin β chain increases in the renal medulla, but not in the renal cortex, of dehydrated rats. This effect occurs only in WAG rats with a normally expressed vasopressin gene and is absent in mutant Brattleboro rats unable to synthesize this hormone. Based on the initial and new data, it is assumed that laminin, as a key regulatory element in the basement membrane of the tubular epithelium, is involved in the adaptive response of the renal urine concentrating system to prolonged dehydration. Hyperhydration does not affect laminin levels in the renal parenchyma.

中文翻译：

---

大鼠肾髓层粘连蛋白对长期脱水的反应

摘要

层粘连蛋白是上皮组织基底膜中主要的水溶性糖蛋白。研究人员在喂食 60 小时替代水饮食、过量饮水或完全缺乏饮用水的大鼠中研究了肾实质的层粘连蛋白含量。结果表明，由于缺水而产生的尿液渗透浓度伴随着层粘连蛋白组成的定量变化。研究发现，脱水大鼠的肾髓质中层粘连蛋白β链的水平增加，但肾皮质中的层粘连蛋白β链水平没有增加。这种效应仅发生在具有正常表达的加压素基因的 WAG 大鼠中，并且在无法合成这种激素的突变型 Brattleboro 大鼠中不存在。根据初始数据和新数据，假设层粘连蛋白，作为肾小管上皮基底膜的关键调节元件，参与肾尿液浓缩系统对长期脱水的适应性反应。过度水合不会影响肾实质中的层粘连蛋白水平。