Seasonal and temperature effects on steady-state ion distributions of Arctic charr (Salvelinus alpinus) erythrocytes

: Lecklin T, Nikinmaa M

Publisher: ELSEVIER SCIENCE INC

: 1999

: Comparative Biochemistry and Physiology - Part A: Molecular and Integrative Physiology

: COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR AND INTEGRATIVE PHYSIOLOGY

: COMP BIOCHEM PHYS A

: 123

: 3

: 287

: 292

: 6

: 1095-6433

DOI: https://doi.org/10.1016/S1095-6433(99)00062-8

The effects of thermal history, temperature changes in vitro and seasonal cycle on the ion contents of Arctic charr erythrocyte in defined medium were studied. The charr was acclimated to three different temperature (2, 8 or 14 degrees C) and the experiments were carried out in winter, spring and summer. Erythrocyte membrane preparations from charr and rainbow trout were used in order to investigate membrane fluidities after acclimation to different temperatures. Acute temperature changes (in vitro) have no effect on charr erythrocytic ion content. In contrast, temperature acclimation changed the intracellular ion composition; cellular water and chloride contents decreased and potassium content increased with increasing acclimation temperature. However, the effect of previous acclimation was seen only in spring. A seasonality of ion contents was evident; there were a reduction in intracellular sodium content and an elevation in chloride content in summer. Both thermal and seasonal effects were independent of extracellular pH. The membrane fluidities of charr and trout did not respond to temperature acclimation, although there were interspecies differences in temperature sensitivity of membrane fluidity (C) 1999 Elsevier Science Inc. All rights reserved.