Gerber J G, Fadul S, Payne N A, Nies A S
J Pharmacol Exp Ther. 1984 Oct;231(1):109-13.
We tested the hypothesis that there are adenosine receptors in the gastric fundus responsible for the modulation of acid secretion to secretagogues. We utilized anesthetized gastric fistula dogs and infused both the secretagogues (histamine, 0.5 microgram/min and methacholine, 1 microgram/min) and adenosine through the gastric artery supplying the fundus of the stomach to avoid systemic effects of the drug. Adenosine infused to a concentration of 30 microM inhibited histamine-stimulated acid secretion from 197 +/- 25 to 68 +/- 19 microEq/15 min and inhibited methacholine-stimulated acid secretion from 280 +/- 48 to 81 +/- 24 microEq/15 min. Intravenously infused theophylline to a plasma concentration of 17 micrograms/ml (94 microM) blocked the inhibitory effect of adenosine on gastric acid secretion but did not affect the inhibitory effect of prostaglandin E2 on gastric acid secretion. In contrast, the specific phosphodiesterase inhibitor RO 20 1724 did not alter the inhibitory effect of adenosine on gastric acid secretion. In addition to its effect on gastric acid secretion, adenosine was found to be a potent vasodilator of gastric blood vessels. Our data suggest that there are inhibitory adenosine "R" receptors in the gastric fundus that modulate acid secretion to both histamine and methacholine.
胃底存在腺苷受体，负责调节对促分泌剂的胃酸分泌。我们使用麻醉的胃瘘犬，通过供应胃底的胃动脉灌注促分泌剂（组胺，0.5微克/分钟和乙酰甲胆碱，1微克/分钟）和腺苷，以避免药物的全身作用。灌注至浓度为30微摩尔的腺苷将组胺刺激的胃酸分泌从197±25微当量/15分钟抑制至68±19微当量/15分钟，并将乙酰甲胆碱刺激的胃酸分泌从280±48微当量/15分钟抑制至81±24微当量/15分钟。静脉内灌注至血浆浓度为17微克/毫升（94微摩尔）的茶碱阻断了腺苷对胃酸分泌的抑制作用，但不影响前列腺素E2对胃酸分泌的抑制作用。相比之下，特异性磷酸二酯酶抑制剂RO 20 1724并未改变腺苷对胃酸分泌的抑制作用。除了对胃酸分泌的作用外，还发现腺苷是胃血管的强效血管扩张剂。我们的数据表明，胃底存在抑制性腺苷“R”受体，可调节对组胺和乙酰甲胆碱的胃酸分泌。
