Document Detail


Role of cyclic guanosine monophosphate in late preconditioning in conscious rabbits.
MedLine Citation:
PMID:  12082001     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND: Although NO has been shown to serve both as the trigger and the mediator of the late phase of ischemic preconditioning (PC), it is unknown whether NO acts via activation of soluble guanylate cyclase (sGC). The objective of this study was to investigate the role of sGC in late PC in conscious rabbits using the selective sGC inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ). METHODS AND RESULTS: A total of 172 conscious rabbits were used. When nonpreconditioned rabbits were subjected to a sequence of 4-minute coronary occlusion/4-minute reperfusion cycles, myocardial cyclic guanosine monophosphate (cGMP) levels increased significantly at the end of the third and sixth occlusions. In rabbits preconditioned 24 hours earlier (on day 1) with six occlusion/reperfusion cycles, myocardial cGMP levels on day 2 were significantly higher than in nonpreconditioned rabbits even before ischemia but did not increase further during a second sequence of 4-minute occlusion/reperfusion cycles. Administration of ODQ before the six occlusion/reperfusion cycles on day 1 did not prevent the development of late PC against either stunning or infarction on day 2. In contrast, administration of ODQ on day 2 completely ablated the late PC effect against both stunning and infarction. CONCLUSIONS: These results indicate that enhanced synthesis of cGMP by sGC is not necessary for ischemia to trigger a late PC effect but is required for the protection to become manifest 24 hours later. This implies that NO participates in late PC via two distinct mechanisms; ie, it triggers late PC on day 1 via a cGMP-independent mechanism and it mediates late PC on day 2 via a cGMP-dependent mechanism.
Authors:
Eitaro Kodani; Yu-Ting Xuan; Hitoshi Takano; Ken Shinmura; Xian-Liang Tang; Roberto Bolli
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Circulation     Volume:  105     ISSN:  1524-4539     ISO Abbreviation:  Circulation     Publication Date:  2002 Jun 
Date Detail:
Created Date:  2002-06-25     Completed Date:  2002-07-08     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  0147763     Medline TA:  Circulation     Country:  United States    
Other Details:
Languages:  eng     Pagination:  3046-52     Citation Subset:  AIM; IM    
Affiliation:
Experimental Research Laboratory, Division of Cardiology, University of Louisville and the Jewish Heart and Lung Institute, Louisville, Ky 40292, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Consciousness
Cyclic GMP / physiology*
Enzyme Inhibitors / pharmacology
Guanylate Cyclase / antagonists & inhibitors
Ischemic Preconditioning, Myocardial*
Kinetics
Male
Myocardial Infarction / enzymology,  metabolism,  prevention & control*
Myocardial Stunning / enzymology,  metabolism,  prevention & control*
Oxadiazoles / pharmacology
Quinoxalines / pharmacology
Rabbits
Grant Support
ID/Acronym/Agency:
HL-55757/HL/NHLBI NIH HHS; HL-65660/HL/NHLBI NIH HHS; HL-68088/HL/NHLBI NIH HHS; R01 HL-43151/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
0/1H-(1,2,4)oxadiazolo(4,3-a)quinoxalin-1-one; 0/Enzyme Inhibitors; 0/Oxadiazoles; 0/Quinoxalines; 7665-99-8/Cyclic GMP; EC 4.6.1.2/Guanylate Cyclase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Sensitivity to apoptosis signal, clearance rate, and ultrastructure of fas ligand-induced apoptosis ...
Next Document:  Polymorphic reentrant ventricular tachycardia in the isolated rabbit heart studied by high-density m...