A HISTOCHEMICAL STUDY OF ADENOSINE TRIPHOSPHATASE IN THE TOAD (BUFO SPINULOSUS) GASTRIC MUCOSA

• Published in: The journal of histochemistry and cytochemistry Vol. 18; no. 5; pp. 340 - 353
• Main Authors: Koenig, C, Vial, J D
• Format: Journal Article
• Language: English
• Published: London, England Histochemical Soc 01-05-1970; SAGE Publications
• Subjects: Adenosine Triphosphatases - analysis; Animals; Anura - anatomy & histology; Bicarbonates - pharmacology; Gastric Acidity Determination; Gastric Juice - secretion; Gastric Mucosa - enzymology; Gastric Mucosa - secretion; Histamine; Histocytochemistry; Magnesium - pharmacology; Microscopy; Microscopy, Electron; Microsomes - metabolism
• ISSN: 0022-1554; 1551-5044
• DOI: 10.1177/18.5.340

Adenosine triphosphatase (ATPase) activity was studied by histochemical methods in the gastric mucosa of Bufo spinulosus. Two types of activity were established. One is activated by Mg++, and is localized mainly at the intercellular boundaries and the basal zone of the oxyntic-peptic cells; the reaction products are found only on the outer side of the cells. The other is activated by HCO3
– and is mainly localized at the microvilli at the apical zone of the oxyntic-peptic cells. The intensity and/or distribution of the reactions are influenced by histamine stimulation. Control experiments demonstrated that: the microsomal fraction of gastric mucosa contained a Mg++-requiring ATPase activity which was enhanced by addition of HCO3
–; 25% of the ATPase activity of fresh tissue was maintained after fixation and incubation in presence of lead ion; the medium employed in the histochemical studies did not enhance the lead-catalyzed, nonenzymatic hydrolysis of ATP by more than 20% when compared with spontaneous ATP hydrolysis; and incubation in media with different ATP-Pb ratios did not significantly alter the location of the staining.