Use this URL to cite or link to this record in EThOS: https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.777439
Title: Characterization of gastric ATPase vesicle transport
Author: Sachs, George
Awarding Body: University of Edinburgh
Current Institution: University of Edinburgh
Date of Award: 1981
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Abstract:
The microsomal fraction of both dog and hog gastric mucosa contains a K⁺ activated ATPase. ATP phosphorylates a peptide of c̅ 100,000 Mᵣ in both species, and dephosphorylation is stimulated by K⁺. By a combination of differential and zonal density gradient centrifugation a membrane fraction is produced containing almost exclusively this peptide region. These vesicles, upon the addition of ATP, take up H⁺ and extrude K⁺. The action of ionophores such as nigericin or valinomycin and the uptake of lipid permeable anions such as thiocyanate or anilino-naphthosulfonic acid indicate the lack of a potential difference during transport. Reconstitution of this material into a planar bilayer indicates that ATP activates a K⁺ conductance and hence, in the presence of K⁺ also a low potential difference is observed. These data suggest that this H⁺ pump is non-electrogenic as prepared in the vesicular form. Using an antibody obtained from rabbits immunized with the highly purified membrane fractions, it was demonstrated that this membrane was derived uniquely from gastric parietal cells. Hence, based on the ability of this ATPase to actively transport H⁺, its cellular origin and on the well known K⁺ requirement for acid secretion in amphibia and mammals, it is concluded that this ATPase is a component of the HCl secretory mechanism of gastric mucosa.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (D.Sc.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.777439  DOI: Not available
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