Comparison of three different A1 adenosine receptor antagonists on infarct size and multiple cycle ischemic preconditioning in anesthetized dogs. J Pharmacol Exp Ther 2004 Mar;308(3):846-56
Date
11/25/2003Pubmed ID
14634049DOI
10.1124/jpet.103.057943Scopus ID
2-s2.0-10744233575 (requires institutional sign-in at Scopus site) 43 CitationsAbstract
A(1) adenosine receptor (AR) antagonists are effective diuretic agents that may be useful for treating fluid retention disorders including congestive heart failure. However, antagonism of A(1)ARs is potentially a concern when using these agents in patients with ischemic heart disease. To address this concern, the present study was designed to compare the actions of the A(1)AR antagonists CPX (1,3-dipropyl-8-cyclopentylxanthine), BG 9719 (1,3-dipropyl-8-[2-(5,6-epoxynorbornyl)]xanthine), and BG 9928 (1,3-dipropyl-8-[1-(4-propionate)-bicyclo-[2,2,2]octyl]xanthine) on acute myocardial ischemia/reperfusion injury and ischemic preconditioning (IPC) in an in vivo dog model of infarction. Barbital-anesthetized dogs were subjected to 60 min of left anterior descending coronary artery occlusion followed by 3 h of reperfusion, after which infarct size was assessed by staining with triphenyltetrazolium chloride. IPC was elicited by four 5-min occlusion/5-min reperfusion cycles produced 10 min before the 60-min occlusion. Multiple-cycle IPC produced a robust reduction ( approximately 65%) in infarct size; this effect of IPC on infarct size was not abrogated in dogs pretreated with any of the three AR antagonists. Surprisingly, in the absence of IPC, pretreatment with CPX or BG 9928 before occlusion or immediately before reperfusion resulted in significant reductions ( approximately 40-50%) in myocardial infarct size. However, treatment with an equivalent dose of BG 9719 had no similar effect. We conclude that the A(1)AR antagonists BG 9719, BG 9928, and CPX do not exacerbate cardiac injury and do not interfere with IPC induced by multiple ischemia/reperfusion cycles. We discuss the possibility that the cardioprotective actions of CPX and BG 9928 may be related to antagonism of A(2B)ARs.
Author List
Auchampach JA, Jin X, Moore J, Wan TC, Kreckler LM, Ge ZD, Narayanan J, Whalley E, Kiesman W, Ticho B, Smits G, Gross GJAuthors
John A. Auchampach PhD Professor in the Pharmacology and Toxicology department at Medical College of WisconsinTina C. Wan PhD Research Scientist II in the Pediatrics department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
Adenosine A1 Receptor AntagonistsAnesthesia
Animals
Disease Models, Animal
Dogs
Ischemic Preconditioning, Myocardial
Myocardial Infarction
Myocardial Ischemia
Myocardial Reperfusion Injury
Radioligand Assay
Receptor, Adenosine A2A
Xanthines