Membrane solvation as a basis for ionic selectivity.
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Cell Membrane Permeability↗
Biomedical subjects
B D Lindley
Publications and source records attributed to B D Lindley.
Phenomenological description of active transport of salt and water.
The phenomenological definition of active transport by Kedem and the methods of Kedem and Katchalsky have been used to obtain practical equations describing active transport in the single salt and bi-ionic systems. Procedures were devised to evaluate the required set of 10 coefficients for the single salt case and 15 for the bi-ionic. Three of these coefficients are unusual. They express the effects of active transport, i.e. of entrainment between metabolism and the conventional transport flows: active salt transport coefficient, a volume pump coefficient, and an electrogenicity coefficient. In the bi-ionic case a new passive coefficient, lambda, was used to express the linkage between the fluxes of the two salts. However, if primary active transport involves only one ion, for example in the bi-ionic case, 12 coefficients suffice and certain relations can be predicted between the practical coefficients. Particular types of primary active transport could be identified by this means. The relation of active transport to membrane electrogenesis was also examined and the flux ratio equation was rederived in terms of the practical coefficients. Applications to specific parallel and series membrane systems have been analyzed.
Animals↗
Potentiometric measurement of membrane action potentials in frog muscle fibres.
1. A potentiometric method for recording membrane action potentials from small segments of isolated skeletal muscle fibres has been described.2. The value of the method in muscle physiology has been appraised by recording from fast and slow skeletal muscle fibres of the frog under a variety of conditions.3. Artifacts associated with this method have been described and their sources investigated.
Animals↗
Interaction between the effects of inside and outside Na and K on bullfrog skin potential.
The composition of the solution bathing one border of the isolated frog skin affects the response of the potential across the skin to changes in the composition of the solution bathing the opposite border. Increasing the K concentration of the inside (corium) bathing solution decreased the sensitivity of the potential to a change in outside Na concentration. Decreasing the outside Na concentration decreased the sensitivity of the potential to a change in inside K concentration. Increasing the total ionic strength of the outside bathing solution or of both bathing solutions decreased the sensitivity of the potential to a change in outside Na concentration.
Animals↗