Distal tubular segments of the rabbit kidney after adaptation to altered Na- and K-intake. I. Structural changes

Cell Tissue Res. 1982;224(3):469-92. doi: 10.1007/BF00213746.

Abstract

The baso-lateral cell-membrane area in kidney tubules appears to be associated with the capacity for electrolyte transport; in the rabbit, it decreases from the distal convoluted tubule (DCT-cells) over the connecting tubule (CNT-cells) to the cortical collecting duct (principal cells). Adaptation to low Na-, high K-intake changes this pattern: CNT-cells at the beginning of the connecting tubule have the highest membrane area, which decreases along the segment, but remains two-fold higher than in controls. Principal cells have a four-fold higher membrane area than in controls. Simultaneous treatment with the antimineralocorticoid canrenoate-K inhibits the structural changes in CNT-cells only in end-portions of the connecting tubule and in principal cells. After prolonged high Na-, low K-intake DCT-cells display a two-fold higher membrane area than controls, while CNT-cells and principal cells are not affected. Simultaneous treatment with DOCA does not affect the DCT-cells but provokes a moderate increase in membrane area in CNT-cells, and a 5.5-fold increase in principal cells. The data provide evidence that DCT-, CNT- and principal cells are functionally different cell types. The baso-lateral cell-membrane area, associated with electrolyte-transport capacity, appears to be influenced in DCT-cells mainly by Na-intake, in CNT-cells mainly by K-intake and in part also by mineralocorticoids, and in principal cells mainly by mineralocorticoids.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Physiological
  • Aldosterone / blood
  • Animals
  • Cell Membrane / ultrastructure
  • Desoxycorticosterone / pharmacology
  • Diet*
  • Diet, Sodium-Restricted
  • Female
  • Kidney Tubules / ultrastructure*
  • Kidney Tubules, Collecting / ultrastructure
  • Kidney Tubules, Distal / ultrastructure*
  • Microscopy, Electron
  • Mitochondria / ultrastructure
  • Potassium / administration & dosage*
  • Potassium / urine
  • Rabbits
  • Sodium / administration & dosage*
  • Sodium / urine

Substances

  • Desoxycorticosterone
  • Aldosterone
  • Sodium
  • Potassium