Infarct Size-limiting Effect of Calcium Preconditioning in Rabbit Hearts.
10.3346/jkms.2003.18.3.337
- Author:
Ho Dirk KIM
1
Author Information
1. Department of Anatomy and Cell Biology, Sungkyunkwan University School of Medicine, Suwon, Korea. hdkim@med.skku.ac.kr
- Publication Type:Original Article ; In Vitro ; Research Support, Non-U.S. Gov't
- Keywords:
Ischemic Preconditioning Myocardial;
Myocardial Infarction;
Reperfusion Injury;
Protein Kinase C;
Rabbits;
Heart
- MeSH:
Animals;
Calcium/*pharmacology;
Cardiotonic Agents/*pharmacology;
In Vitro;
*Ischemic Preconditioning, Myocardial;
Isoenzymes/metabolism;
L-Lactate Dehydrogenase/metabolism;
Male;
Myocardial Infarction/*pathology;
Myocardium/enzymology/pathology;
Protein Kinase C/metabolism;
Rabbits
- From:Journal of Korean Medical Science
2003;18(3):337-343
- CountryRepublic of Korea
- Language:English
-
Abstract:
Recent studies demonstrated that brief period of Ca2+ depletion and repletion (Ca2+ preconditioning, CPC) has strong protective effects against ischemia in a rat heart. CPC and classic preconditioning (IPC) were compared in relation with infarct size and protein kinase C (PKC) isozymes. Isolated Langendorff-perfused rabbit hearts were subjected to 45-min ischemia (Isc) followed by 120-min reperfusion (R) with or without IPC, induced by 5-min Isc and 10-min R. In the CPC hearts, 5-min Ca2+ depletion and 10-min repletion (CPC) were given before 45-min Isc, with or without concurrent PKC inhibition (calphostin C, 200 nmol/L). IPC enhanced recovery of LV function, while CPC did not. Infarct size was significantly reduced by both CPC and IPC (p < 0.05 vs. ischemic control). Membrane PKC was significantly increased from 2.53 +/- 0.07 (baseline, nmol/g tissue) to 3.11+/-0.07, 3.34 +/- 0.11, 3.15 +/- 0.09, and 3.06 +/- 0.08 by IPC, IPC and 45-min Isc, CPC and 45-min Isc, respectively (p < 0.01). Immunoblots of membrane PKC were increased by IPC, IPC and 45-min Isc, and CPC. These effects were abolished by PKC inhibition. Thus, activation of PKC may have trigger role in the mechanism of cardioprotective effect by CPC.
