The distribution of penetrating ammonium salts between cells and their surroundings

✍ Scribed by Jacobs, M. H. ;Stewart, Dorothy R.

• Publisher: Wiley (John Wiley & Sons)
• Year: 1936
• Tongue: English
• Weight: 785 KB
• Volume: 7
• Category: Article
• ISSN: 0095-9898
• DOI: 10.1002/jcp.1030070305

✦ Synopsis

a d #kidmore College TWO FIGURES

I

The ability of the ammonium salts of various acids to enter living cells usually parallels rather clasely that of the free acids from which they are derived. Thus, the acetate, bicarbonate, benzoate and other similar salts of weak acids penetrate all cells with great ease, while the chloride, nitrate and sulphate apparently do so no more readily than the corresponding potassium and sodium salts, except in the case of the erythrocyte whose behavior in this respect is unique. Among the ammonium salts of weak acids an instructive series is furnished by those of the first five saturated fatty acids which show the order predictable from the behavior of the free acid, namely: formate<acetate<propionate<buty-rate<valerate, with cells of as diverse nature as the mammalian erythrocyte (Jacobs, '27), the egg of Arbacia (Stewart, '31) and cells of the plants Tradescantia and Allium (Bouillenne, '30).

A plausible explanation of these facts (Jacobs, '24, '27) is that what enters the cell from a solution of an ammonium salt of a weak acid is neither the salt itself nor its ions, but rather the products of its hydrolysis, free NH, and free acid, these substances subsequently recombining within the cell to form the original salt as in Q of figure 1. I n the case of salts 351 '22 ; Blinks, '34) without any important osmotic volume changes (see b of fig. 1). Only in the erythrocyte, which with the possible exception of the leucocyte seems to be unique among cells in being readily permeable to anions, is there a possibility, following the entrance of NH,, of an exchange of anions and therefore of a continuous transfer of salt from