Journalartikel

Jahr der Veröffentlichung: 1988

Seiten: 193-198

Zeitschrift: Journal of Plant Physiology

Bandnummer: 133

Heftnummer: 2

ISSN: 0176-1617

DOI Link: https://doi.org/10.1016/S0176-1617(88)80136-6

Verlag: Elsevier

Abstract: 

The mechanism of Na+ efflux from roots was investigated using intact seedlings of Zea mays L. cv. Pioneer 3906. 22Na+ efflux was independent of external Na+ but stimulated by K+. Low temperature (4°C) and the Ca2+ chelator, ethyleneglycol-bis-(β-aminoethyl ether) N,N1,N1-tetraacetic acid (EGTA), increased 22Na+ efflux. The protonophore and uncoupler, carbonylcyanide-3-chlorophenylhydrazone (CCCP), and the sulfhydryl reagent, N-ethylmaleimide (NEM), did not affect 22Na+ efflux during the initial 60 minutes. Except for Na+, which transiently depolarized the membrane potential, a permanent depolarization was observed with all treatments, causing a change in the electro-chemical driving force for Na+.
The data allowed to distinguish between two cytoplasmic Na+ efflux components: an active component depending on metabolic energy and a passive one driven by the electro-chemical potential difference for Na+. Since both components counteract each other when metabolism is inhibited (e.g. by CCCP or NEM), metabolic dependence of Na+ efflux from maize roots can only by estimated indirectly taking into account the change in the electro-chemical potential difference for Na+.

Harvard-Zitierstil: Schubert, S. and Läuchli, A. (1988) Metabolic Dependence of Na+ Efflux from Roots of Intact Maize Seedlings, Journal of Plant Physiology, 133(2), pp. 193-198. https://doi.org/10.1016/S0176-1617(88)80136-6

APA-Zitierstil: Schubert, S., & Läuchli, A. (1988). Metabolic Dependence of Na+ Efflux from Roots of Intact Maize Seedlings. Journal of Plant Physiology. 133(2), 193-198. https://doi.org/10.1016/S0176-1617(88)80136-6