The human erythrocyte data

The treatment of Collander s data on the permeation into giant algal cells has occasioned little controversy. But a similar treatment of the now extensive data on permeation into human red blood cells raises a number of problems on which researchers in the field have as yet not reached general agreement. 

There are a number of reasons why the human red cell data are less tractable than those for plant cells. In the first place, the cells in question come from a species which is almost certainly more highly evolved than the primitive algae studied by Collander the membranes of the human red cell contain numerous specialised transport systems. The data on specialised systems should be set apart from the remaining data if the interaction between solute structure and simple diffusion properties of the membrane is to be investigated. Excellent evidence exists that the uptake of glycerol into human red cells occurs by a specialised system [1,14] which 

Data on an ascending homologous series of permeants provide an instructive choice of model solutes since with such a series, it is merely the length of the molecule that increases with molecular weight, the cross-sectional area of the molecule remaining unaltered. It has been clearly established for the diffusion of 

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