Van Harn G L, Rubio R, Berne R M
Am J Physiol. 1977 Aug;233(2):H299-304. doi: 10.1152/ajpheart.1977.233.2.H299.
Media strips of hog carotid artery formed hypoxanthine and inosine during incubation under conditions of normoxia (95% O2, 5% CO2). During anoxia (95% N2, 5% CO2), hypoxanthine increased fivefold and inosine twofold. Stimulation with 124 mM K+ resulted in a twofold increase in hypoxanthine and a threefold increase in inosine. Concurrent with the increase in the concentrations of purine derivatives was a decrease in tissue ATP. Although significant amounts of adenosine were not detected in the medium of incubating artery strips, the following evidence suggests adenosine was formed and rapidly deaminated to inosine: 1) Exogenous adenosine added to the medium of incubating strips was rapidly deaminated to inosine. 2) Exogenous 5'-AMP concentration decreased, whereas adenosine and, subsequently, inosine levels increased during incubation of artery strips. The reaction was specific for 5'-AMP and the data suggest that AMP is dephosphorylated to adenosine. 3) The specific activity of exogenous [U-14C]adenosine added to the medium of incubated strips decreased after 15 min. It is concluded that adenosine is formed in isolated artery strips but is rapidly deaminated to inosine.
猪颈动脉的血管条在常氧（95% O₂，5% CO₂）孵育条件下会形成次黄嘌呤和肌苷。在缺氧（95% N₂，5% CO₂）状态下，次黄嘌呤增加了五倍，肌苷增加了两倍。用124 mM K⁺刺激导致次黄嘌呤增加两倍，肌苷增加三倍。嘌呤衍生物浓度增加的同时，组织ATP减少。尽管在孵育的血管条培养基中未检测到大量腺苷，但以下证据表明腺苷已形成并迅速脱氨生成肌苷：1）添加到孵育条培养基中的外源性腺苷迅速脱氨生成肌苷。2）在血管条孵育期间，外源性5'-AMP浓度降低，而腺苷以及随后的肌苷水平升高。该反应对5'-AMP具有特异性，数据表明AMP被去磷酸化生成腺苷。3）添加到孵育条培养基中的外源性[U-¹⁴C]腺苷在15分钟后比活性降低。结论是腺苷在分离的血管条中形成，但会迅速脱氨生成肌苷。
