PT - JOURNAL ARTICLE AU - ALFRED M. WEDD TI - THE ACTION OF ADENOSINE AND CERTAIN RELATED COMPOUNDS ON THE CORONARY FLOW OF THE PERFUSED HEART OF THE RABBIT DP - 1931 Mar 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 355--366 VI - 41 IP - 3 4099 - http://jpet.aspetjournals.org/content/41/3/355.short 4100 - http://jpet.aspetjournals.org/content/41/3/355.full SO - J Pharmacol Exp Ther1931 Mar 01; 41 AB - 1. Adenosine acts as a powerful dilator on the coronary vessels of the perfused heart of the rabbit. The dilatant effect is independent of change in rate and the action of that substance on the cardiac muscle. 2. Adenosine is approximately twenty times as powerful a vasodilator as sodium nitrite, not only in dilating normal vessels but also those that have been constricted by pitressin or barium chloride. 3. Adenylic acid obtained from yeast or from muscle is an effective coronary dilator, though somewhat less active than adenosine. Although yeast adenylic acid has a comparatively feeble action on the sinus and junctional tissues, its dilatant action is equal to that of muscle adenylic acid. Adenine and guanosine also dilate the coronary vessels. 4. The similar dilatant effects produced by yeast adenylic acid muscle adenylic acid, and adenosine and the lack of correspondence with direct muscle effects suggest that the dilatant action is produced by an independent mechanism. 5. The hearts of animals suffering from hypervitaminosis due to feeding an excess of vitamin D were perfused and the effect of adenosine was observed. The vessels showed an abnormal reactivity, expressed by a tendency to become nonreactive in a state of dilation much earlier than did the vessels of normal hearts. The type of reaction could not be correlated with histologic changes.