ISSN:
1432-2013
Keywords:
Na+−K+ pump
;
22Na+-efflux
;
Adrenaline
;
Frog skeletal muscle
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract The22Na+-efflux from skeletal muscle cells of frog (Rana nigromaculata) was measured in Ringer solutions containing different concentrations of K+ (0.1 to 30 mM). The effects of adrenaline (30 μM) and ouabain (10 μM) on the22Na+-efflux were investigated for the purpose to clarify the mechanism of the facilitatory effect of adrenaline on Na+−K+ pump. The rate coefficient for the ouabain-sensitive22Na+-efflux increases with increasing extracellular K+ concentrations and adrenaline potently facilitates these rate coefficients. On the basis of Michaelis-Menten type kinetics assumed for the reaction between pump site and extracellular K+, it is concluded that adrenaline decreases the dissociation constant (Km), and increases the maximum Na+-efflux.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00584316
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