CA REGULATION IN THE FRESH-WATER BIVALVE ANODONTA-IMBECILIS .1. EFFECT OF ENVIRONMENTAL CA CONCENTRATION AND BODY-MASS ON UNIDIRECTIONAL AND NET CA FLUXES

Authors
XU DZ WHEATLY MG
Citation
Dz. Xu et Mg. Wheatly, CA REGULATION IN THE FRESH-WATER BIVALVE ANODONTA-IMBECILIS .1. EFFECT OF ENVIRONMENTAL CA CONCENTRATION AND BODY-MASS ON UNIDIRECTIONAL AND NET CA FLUXES, Malacologia, 38(1-2), 1996, pp. 59-65
Citations number
19
Categorie Soggetti
Zoology
Journal title
Malacologia → ACNP
ISSN journal
00762997
Volume
38
Issue
1-2
Year of publication
1996
Pages
59 - 65
Database
ISI
SICI code
0076-2997(1996)38:1-2<59:CRITFB>2.0.ZU;2-Y
Abstract
The present paper reports unidirectional and net Ca fluxes of a freshw ater bivalve, Anodonta imbecilis, as a function of external Ca concent ration and body mass. Larger animals were better able to maintain Ca b alance than smaller animals, which experienced net loss of Ca. Externa l Ca concentration had no significant effect on net Ca flux. Unidirect ional Ca influx decreased with body mass and increased with external C a concentration. The relationship between external Ca concentration an d unidirectional Ca influx follows the Michaelis-Menten equation. The estimated half saturation Ca concentration for unidirectional Ca influ x and the maximum unidirectional influx were 0.213 mM and 4.329 mu mol g dry mass(-1)h(-1), respectively. External Ca concentration did not affect unidirectional Ca efflux of the animals. Unidirectional Ca effl ux decreased with body mass.