Balance of Purine Nucleotides and Catabolites in the Isolated Ischemic Rat Heart
Myocardial contraction depends fully on purine nucleotides (ATP) and creatine phosphate (CrP). The oxygen dependent formation and the breakdown of ATP are in a delicately regulated balance. During ischemia oxygen supply is lowered, ATP-levels fall and the heart releases catabolites of purine nucleotides, probably to maintain an adequately high energy charge. Released are uric acid (UA), xanthine (X), hypoxanthine (Hx), inosine (Ino) and adenosine (Ado). Amongst these, adenosine is very important because of its coronary vasodilating properties (1). Maintenance of adequate levels of purine nucleotides occurs not only by (slow) de novo synthesis, but also by phosphorylation of Ado and salvage of Hx.
KeywordsUric Acid High Pressure Liquid Chromatography Adenine Nucleotide Purine Nucleoside Purine Nucleotide
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