Adenosine triphosphatases (ATP-A) on sensory cell plasmic membranes of tuberous organs (electroreceptors) of Gnathonemus petersii (Mormyridae) . Cytochemical study
Denizot, J.P.
Cellular and Molecular Biology Including Cyto-Enzymology 26(6): 653-662
1980
ISSN/ISBN: 0145-5680 PMID: 6452211 Document Number: 159002
ATPase in the electroreceptive sensory cells of the tuberous organ of the Mormyrid, G. petersii, is examined. Mg2+ (Na+K+)-dependent ATPase was demonstrated by the Mac Clurkin method. With the aid of this technique the enzyme was localized in the plasma membrane of sensory cells. Conditions preserving good conservation of the enzyme by the fixators, and resistence to inhibitors (NaF 12.5 mM, ouabain 1 and 2.5 mM) were sought. By replacing Na+ and K+ by Ca2+ in the incubation solution, the presence of another enzyme, Mg2+ Ca2+-dependent ATPase, was demonstrated in the plasma membrane of certain cells. Mg2+ Ca2+-dependent ATPase may ensure the transport of Ca2+ across the membrane, which is responsible for the electrical activity produced by the tuberous organ sensory cells.