8-Bromo cyclic GMP inhibits NADH and lactate accumulation in hypoxic rat atria.
The effects of 8-bromo-cGMP on tissue lactate and NADH levels were studied under conditions of high oxygen saturation (95-100%) and hypoxia (50%) in spontaneously beating rat atria. The induction of hypoxia caused a rapid decline in contractility with a simultaneous increase in tissue lactate and NADH. 8-bromo-cGMP (10(-4) mol/l) prevented the accumulation of lactate occurring during hypoxia. It also lowered the level of lactate during high oxygen saturation. Furthermore, 8-bromo-cGMP inhibited the hypoxia-induced increase in NADH and lowered the level of NADH in high oxygen saturation. 8-bromo-cGMP did not affect contractility or heart rate during hypoxia. It is concluded that cGMP may influence the redox-state and metabolism in a direction which is beneficial for the hypoxic myocyte. It is also suggested that antianginal nitro compounds which enhance the level of cGMP might exert an effect similar to that of 8-bromo-cGMP.
D000818:Animals; D003327:Coronary Disease / Q000378:metabolism*; D006152:Cyclic GMP / Q000031:analogs & derivatives* / Q000494:pharmacology; D066298:In Vitro Techniques; D007773:Lactates / Q000378:metabolism*; D019344:Lactic Acid; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D009243:NAD / Q000378:metabolism*; D010101:Oxygen Consumption / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains
D007773:Lactates; D009243:NAD; C016276:8-bromocyclic GMP; D019344:Lactic Acid; D006152:Cyclic GMP