Abstract
A number of workers have studied the chemical composition of certain tissues, notably skeletal muscle, after adrenalectomy [Hegnauer & Robinson, 1936; Harrison & Darrow, 1938; Darrow, Harrison & Taffel, 1939; Muntwyler, Mellors & Mautz, 1940; Conway & Hingerty, 1946] and a general theory relating the intracellular and extracellular electrolyte concentrations, the intracellular non-diffusible molecule concentration (the idiomolar value), the algebraic sum of the charges on such molecules (the electrostatic equivalent) and the relative volume of the cells, has been developed by Conway & Boyle [1939], Boyle & Conway [1941] and Conway [1945]. Estimates of the idiomolar value, η, and the electrostatic equivalent, ε, may be obtained from the intracellular potassium and chloride ion concentrations, the total external molecular concentration and the intra- and extracellular fluid volumes [Conway & Hingerty, 1946]. The present paper is particularly concerned with the non-diffusible molecule content of skeletal muscle, liver and testis, and with the