The permeation of water into chick heart fibroblasts in tissue culture

Abstract

By employing the technique of immersion refractometry to measure volume changes, a study has been made of the rate of entry of water into chick heart fibroblasts cultured in a fluid medium. The time required for the cytoplasm of the fibroblast to reach a given refractive index, when the cell is exposed to a low external osmotic pressure, is a measure of its permeability. It is pointed out that all calculations applied to such data depend on various more or less arbitrary assumptions. A number of calculations made on different assumptions give estimates of the permeability coefficient for the cell membrane varying from 1.41 to 2.82 μ min -1 atm -1 at 38°C, or on the other hand, estimates of the diffusion coefficient of water in the protoplasm varying from 1.7 x 10 -10 to 6.6 x 10 -10 cm 2 /s.