Role of gastric glandular mucosal energy metabolism in cold-restraint gastric lesion formation.
The effects of cold and restraint and of some of the antiulcer drugs on adenosine nucleotide content in the gastric glandular mucosa were examined. A bioluminescence technique was used to measure the amount of ATP and its metabolites in gastric mucosal tissue. Cold-restraint produced gastric lesions and increased the gastric mucosal ATP. Verapamil pretreatment attenuated these lesions and further intensified the ATP increase in a dose-related manner. The ATP/ADP ratio and the Atkinson index were also elevated. Calcium gluconate produced similar effects. Atropine or EGTA pretreatment protected or worsened the gastric lesion, respectively, but did not have any influence on the changes in mucosal energy metabolism. Ranitidine pretreatment lessened the lesion formation but had no influence on the nucleotide content. These findings indicate that the metabolic rate of the gastric mucosa is suppressed during cold-restraint conditions; this depression is probably due to hypothermia and reduction of mucosal metabolism. The lesion-protecting mechanisms of the drugs do not seem to be mediated through their effects on mucosal energy metabolism. The oxygen- and ATP-sparing effects of verapamil may contribute partly to its gastro-protective effect.
Koo
M W
MW
Department of Pharmacology, Faculty of Medicine, University of Hong Kong.
Cho
C H
CH
Ogle
C W
CW
D000244:Adenosine Diphosphate / Q000032:analysis; D000249:Adenosine Monophosphate / Q000032:analysis; D000255:Adenosine Triphosphate / Q000032:analysis; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002125:Calcium Gluconate / Q000494:pharmacology; D003080:Cold Temperature / Q000009:adverse effects; D000242:Cyclic AMP / Q000032:analysis; D004533:Egtazic Acid / Q000494:pharmacology; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology*; D005260:Female; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism*; D011899:Ranitidine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013276:Stomach Ulcer / Q000209:etiology / Q000378:metabolism*; D014700:Verapamil / Q000494:pharmacology
D000249:Adenosine Monophosphate; D004533:Egtazic Acid; D000244:Adenosine Diphosphate; D001285:Atropine; D011899:Ranitidine; D000255:Adenosine Triphosphate; D014700:Verapamil; D000242:Cyclic AMP; D002125:Calcium Gluconate