Accession Number:

AD0680610

Title:

PROPERTIES OF SODIUM AND POTASSIUM ACTIVATED ADENOSINE TRIPHOSPHATASES OF RAT BRAIN: EFFECT OF CYCLOPROPANE AND OTHER AGENTS MODIFYING ENZYME ACTIVITY,

Descriptive Note:

Corporate Author:

NAVAL RADIOLOGICAL DEFENSE LAB SAN FRANCISCO CALIF

Personal Author(s):

Report Date:

1968-11-12

Pagination or Media Count:

25.0

Abstract:

Two ATP-hydrolyzing enzyme systems ATPases, possibly lipoprotein in nature, have been isolated from particulate fractions of rat cerebral cortex homogenates. They consist of at least two components, one Mg2 dependent and the other Mg2, Na and K dependent. ATP hydrolysis is measured both by orthophosphate and hydrogen ion liberation. A lack of stoichiometry exists H ion release 2X orthophosphate formation over the first 90 seconds of the reaction. H ion and phosphate release are sensitive to strophanthin, but only in the presence of Na and K. Sulfyhdryl inhibitors including p-hydroxymercuribenzoate POMB and iodoacetate IAA inhibit both basic and Na-K activated ATP hydrolysis, but the enzyme system is more resistant to N-ethylamaleimide NEM, especially the initial spurt of H ion release. Certain gases have an action on enzyme activity, both to decrease cyclopropane or increase it air, nitrogen at pressures above 1 atmosphere. The significance of the lack of stoichiometry between H ion and orthophosphate release and the action of inhibitory agents is discussed. Author

Subject Categories:

  • Biochemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE