Solubilization of Rat Kidney Plasma Membrane Proteins Associated with ³H-Aldosterone

Summary

The treatment of rat kidney plasma membranes with sodium dodecyl sulphate (SDS) did not essentially affect the ability of the membranes for ³H-aldosterone binding as compared with the intact plasma membranes (Ozegovic et al., 1977). A gel filtration of ³H-aldosterone — kidney plasma membranes complex on Sepharose 6B yielded 2 protein and 2 ³H-aldosterone peaks. The proteins which were eluted in the first peak were associated with the first ³H-aldosterone peak while the second ³H-aldosterone peak was eluted with Ve corresponding to Ve of free ³H-aldosterone.

Spironolactone, a competitive antagonist of aldosterone, prevented the binding of ³H-aldosterone to the membrane proteins.

The results demonstrated a high affinity of the kidney plasma membranes solubilized with SDS and a specificity of aldosterone binding to the plasma membrane proteins of higher molecular mass.

Key words

Aldosterone - Kidney - Plasma membrane proteins