Effects of divalent cations on amino acid and divalent cation fluxes in gills of the bivalve mollusc,Mytilus californianus

✍ Scribed by Swinehart, James H. ;Crowe, John H. ;Giannini, Albert P. ;Rosenbaum, David A.

• Publisher: John Wiley and Sons
• Year: 1980
• Tongue: English
• Weight: 588 KB
• Volume: 212
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.1402120311

✦ Synopsis

Abstract

Effects of the deletion of Ca^++^, Mg^++^, or Ca^++^ and Mg^++^ on the leakage of primary amines, Ca^++^, and Mg^++^ from gills of Mytilus californianus were studied. In the absence of Ca^++^ the gills leak primary amines and Ca^++^ for about 30 minutes, after which the primary amines are reabsorbed. In the absence of Mg^++^ the gills leak primary amines, with no net reabsorption for at least 90 minutes, and show rapid leakage of Mg^++^. In the absence of both Ca^++^ and Mg^++^ amino acid leakage is initially less than in the absence of only one of the cations. Measurements of the kinetics of leakages of Ca^++^ and Mg^++^ are consistent with the hypothesis that both ions are associated with the cell surface, but the affinity of Ca^++^ for the cell surface is greater than that of Mg^++^.

In the absence of Mg^++^, the influx of ^14^C‐glycine was depressed to about 1/3 that seen in controls, while deletion of Ca^++^ had no effect on the rate of influx. Increasing the [Mg^++^] stepwise between 5 × 10^−6^ and 1 × 10^−1^ M results in a sigmoidal increase in the rate of influx of ^14^C‐glycine and a hyperbolic increase in the y‐intercept of influx curves.