The hypothesis that insulin and vasopressin increase the permeability of cells to water and water-soluble substances by decreasing the adsorption of Ca2+ at the outer surface of the plasma membrane was tested in a model system. Changes in the specific resistance to the evaporation of water through monoöctadecyl phosphate (mOP) monolayers were compared with simultaneous changes in Ca2+ adsorption. Insulin and vasopressin cause a decrease in the resistance (or, alternatively, increase the transport of water) which can be accounted for only in part by the inhibition of Ca2+ adsorption. The action is specific for these hormones and dependent on interaction between the hormone and monolayer molecules.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Surfaces, Coatings and Films
- Colloid and Surface Chemistry