Abstract
The isolated rat heart is perfused with adenosine-8-C14, or a mixture of ATP-8-C14 and ATP-γ-P32 of known isotope (C14/P32) ratio. The results indicate that any difference between the rate of incorporation of adenosine-C14 or ATP-C14 into myocardial nucleosides and nucleotides fraction did not show significance, and also that any difference of the C14 distribution in the perfusates between adenosine-C14 and ATP-C14 perfused by the isolated rat hearts did not show singnificance.
When perfused with C14-and P32-ATP of known isotope ratio, ATP isolated from the myocardium showed an isotope ratio (C14/P32) approximately 5 times greater than that of ATP in perfusion fluid.
These results suggest that ATP might be first degraded and later resynthesized intracellularly.
