Changes in gastric mucosal content of adenosine, xanthine and hypoxanthine induced by restrained water immersion stress: antiulcer effects of tetraprenylacetone.
The purpose of this study was to clarify the involvement of adenine nucleotide metabolism and substrates of the xanthine-xanthine oxidase system as the source of oxygen free radicals in a rat model of restrained water immersion stress ulceration. The gastric mucosal concentrations of adenine-5'-triphosphate (ATP), adenine-5'-diphosphate (ADP), adenine-5'-monophosphate (AMP) and thiobarbituric-acid (TBA)-reactant substances were measured after 4, 8 and 12 h restrained water immersion stress. The gastric mucosal concentrations of the nucleoside adenosine, the purine bases xanthine and hypoxanthine, and the final metabolic product uric acid, were measured after 4 h of restrained water immersion stress. The concentrations of ATP diminished significantly after 4, 8 and 12 h of restrained water immersion stress. However, the observed stress-induced changes in ADP were not significant. AMP concentrations increased significantly after 4, 8 and 12 h of stress. The adenylate pool (ATP + ADP + AMP) dropped significantly from the prestress value after 4, 8 and 12 h of stress, and the concomitant energy charge (EC = ATP + 0.5 ADP/ATP + ADP + AMP) decreased significantly after 4 and 8 h of stress compared with the prestress value. Gastric mucosal concentrations of TBA-reactant substances displayed a significant increase after 4 h of stress, and remained unchanged after 8 and 12 h of stress from the level after 4 h. Four hours of restrained water immersion stress induced an increase in adenosine and uric acid concentrations and a decrease in the hypoxanthine concentration of the gastric mucosa.(ABSTRACT TRUNCATED AT 250 WORDS)
Itoh
Y
Y
Department of Emergency and Critical Care Medicine, Kansai Medical University, Moriguchi, Japan.
Suzuki
K
K
Matsubara
M
M
Takeyama
N
N
Kitazawa
Y
Y
Tanaka
T
T
D000227:Adenine Nucleotides / Q000032:analysis*; D000241:Adenosine / Q000032:analysis*; D000818:Animals; D000897:Anti-Ulcer Agents / Q000627:therapeutic use*; D004224:Diterpenes / Q000627:therapeutic use*; D005609:Free Radicals; D005753:Gastric Mucosa / Q000737:chemistry*; D019271:Hypoxanthine; D007042:Hypoxanthines / Q000032:analysis*; D007101:Immersion / Q000503:physiopathology; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013276:Stomach Ulcer / Q000188:drug therapy / Q000209:etiology / Q000378:metabolism*; D013312:Stress, Physiological / Q000150:complications*; D013997:Time Factors; D019820:Xanthine; D014970:Xanthines / Q000032:analysis*
D000227:Adenine Nucleotides; D000897:Anti-Ulcer Agents; D004224:Diterpenes; D005609:Free Radicals; D007042:Hypoxanthines; D014970:Xanthines; D019820:Xanthine; D019271:Hypoxanthine; D000241:Adenosine; C031049:geranylgeranylacetone