The effects of cyclic AMP and cyclic GMP on redox state and energy state in hypoxic rat atria.
The effects of 8-bromo-cAMP (10(-4)M) and 8-bromo-cGMP (10(-4)M) on tissue lactate, NADH, creatine phosphate (CP), ATP, ADP and AMP were studied in hypoxic (50% oxygen saturation) spontaneously beating rat atria. CP/ATP ratio and energy charge (EC) were also calculated. In hypoxic rat atria there was a significant increase in tissue lactate, NADH, ADP and AMP and a decrease in CP, CP/ATP ratio and EC. 8-bromo-cGMP abolished these hypoxia-induced changes. The levels of lactate and NADH decreased and those of CP, ATP, ADP and EC increased after administration of 8-bromo-cGMP. 8-bromo-cAMP increased the level of lactate during hypoxia, but did not affect the other hypoxia-induced changes. The present work indicates that cyclic GMP can change the redox state and energy state in a more favourable direction for the hypoxic rat heart.
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology*; D000227:Adenine Nucleotides / Q000378:metabolism; D000818:Animals; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000494:pharmacology; D004734:Energy Metabolism / Q000187:drug effects*; D006325:Heart Atria / Q000378:metabolism; D000860:Hypoxia / Q000378:metabolism*; D007773:Lactates / Q000378:metabolism; D019344:Lactic Acid; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D010084:Oxidation-Reduction; D010725:Phosphocreatine / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D000227:Adenine Nucleotides; D007773:Lactates; D010725:Phosphocreatine; D009243:NAD; D015124:8-Bromo Cyclic Adenosine Monophosphate; C016276:8-bromocyclic GMP; D019344:Lactic Acid; D006152:Cyclic GMP