PERMEATION AND DIFFUSION OF K IONS IN FROG MUSCLE

• DOI: 10.1085/jgp.41.1.169
• Publication Date: 2004-05-13T21:41:10Z
• Authors: E. J. Harris
• Keywords: Strophanthin; Lability; TRACER

The movements of tracer K and net changes have been measured in frog muscle. quantities moving can be linearly related to the square root time after a delay 4 30 minutes depending on external concentration. slope uptake-t((1/2)) line is increased when concentration raised. Q(10) uptake about 1.9 per unit t((1/2)). from 1 2 mM diminished by factor if strophanthin applied. output t((1/2)) 1.4 strophanthin. Tetrabutylammonium substituted for 10 cent Na medium causes reversible slowing output. rates movement found experiments used calculate losses taking place K-free or strophanthin-containing media. results are interpreted basis being limited both resistive outer layer diffusion within K-rich region. internal constant 10(-11) 10(-10) cm.(2) sec.(-1) rate electrochemical activity ion, lability sites which it absorbed, cation + anion pair cell. surface resistance ions accounted as sum membrane equal that electrical methods offered an annulus sufficiently thick (ca. 3 micro) accommodate cell at density mean through diffuses with same holds movement, assumed take ions, has agrees well observed values. influence tetrabutylammonium ion result these agents causing expansion non-selective region, normally occupied mainly Na, expense inner