The effects of adenine nucleotide perfusion on interstitial adenosine production in rat skeletal muscle

摘要

The purpose of the present study was to utilize the microdialysis technique in rat skeletal muscle to perfuse varying concentrations of AMP, ADP, and ATP into the interstitium to examine the effects that these adenine nucleotides have on the production of adenosine in the interstitial space. Interstitial adenosine production appears to be related to the type (ATP, ADP, or AMP) and concentration (2-60 mu mol/L) of the adenine nucleotide perfused. Interstitial adenosine levels increased (P 0.05) from baseline (0.18 +/- 0.02 and 0.22 +/- 0.02 mu mol/L) to 0.23 +/- 0.02 and 0.41 +/- 0.05 mu mol/L following 5 and 30 mu mol/L AMP perfusion, respectively. Similarly, perfusion with 30 mu mol/L ADP and 30, 40, and 60 mu mol/L ATP resulted in an increase (P 0.05) in interstitial adenosine concentration from baseline (0.25 +/- 0.02, 0.26 +/- 0.02, 0.19 +/- 0.03, and 0.14 +/- 0.02 mu mol/L) to 0.30 +/- 0.02, 0.32 +/- 0.02, 0.36 +/- 0.04, and 0.33 +/- 0.04 mu mol/L, respectively. Interestingly, the most prominent increase in interstitial adenosine production occurred during the perfusion of 60 mu mol/L ATP (126% increase from baseline). These data strongly suggest that interstitial ATP may play a more potent role in stimulating interstitial adenosine production as compared with ADP or AMP. In addition, interstitial adenosine production can occur independent of muscle contraction (voluntary or involuntary) or hypoxia when adequate concentrations of adenine nucleotides are available.