alexa Preconditioning protects ischemic rabbit heart by protein kinase C activation.


Journal of Microbial & Biochemical Technology

Author(s): Ytrehus K, Liu Y, Downey JM

Abstract Share this page

Abstract Myocardial protection in the rabbit induced by ischemic preconditioning is thought to be adenosine receptor linked, but the signaling pathway responsible for the protection has yet to be identified. This study tests whether protein kinase C could be involved. Either of two inhibitors of protein kinase C, staurosporine (50 micrograms/kg) or polymyxin B (24 mg/kg), were administered to rabbits subjected to 30 min regional myocardial ischemia followed by 180 min reperfusion. Half of the rabbits were preconditioned while the other half served as nonpreconditioned controls. Nonpreconditioned hearts without drug or treated with staurosporine or polymyxin B resulted in 37.8 +/- 3.1, 40.5 +/- 2.8, and 42.0 +/- 7.0\% infarction of the risk zone, respectively. Preconditioning limited infarct size to 7.3 +/- 2.7\%. Both inhibitors blocked protection in preconditioned hearts with 36.2 +/- 2.7 and 40.9 +/- 2.5\% of the risk zone infarcted, respectively. Activation of protein kinase C with 4 beta-phorbol 12-myristate 13-acetate (PMA) or with 1-oleyl-2-acetyl glycerol (OAG) mimicked preconditioning in buffer-perfused hearts. PMA (0.01 nmol/min) or OAG (10 nmol/min) for 5 min was followed by 10 min of washout. Infarct size after 30 min regional ischemia was limited in the PMA and OAG groups (6.4 +/- 1.4 and 11.7 +/- 3.3 vs. 28.0 +/- 4.5\% in untreated controls) and was equipotent with ischemic preconditioning (11.8 +/- 2.2\%). Polymyxin B also blocked protection from ischemic preconditioning in the isolated heart (33.0 +/- 5.0\%).(ABSTRACT TRUNCATED AT 250 WORDS)
This article was published in Am J Physiol and referenced in Journal of Microbial & Biochemical Technology

Relevant Expert PPTs

Relevant Speaker PPTs

Recommended Conferences

Relevant Topics

Peer Reviewed Journals
Make the best use of Scientific Research and information from our 700 + peer reviewed, Open Access Journals
International Conferences 2017-18
Meet Inspiring Speakers and Experts at our 3000+ Global Annual Meetings

Contact Us

© 2008-2017 OMICS International - Open Access Publisher. Best viewed in Mozilla Firefox | Google Chrome | Above IE 7.0 version