Premium
Brain natriuretic peptide reverses the effects of myocardial stunning in rabbit myocardium
Author(s) -
Anyadike Chukwuma,
Scholz Peter M.,
Katz Elizabeth,
Zhang Qihang,
Weiss Harvey R.
Publication year - 2006
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.20.4.a317-c
Subject(s) - stunning , myocardial stunning , medicine , cardiology , contraction (grammar) , brain natriuretic peptide , natriuretic peptide , ischemia , atrial natriuretic peptide , myocyte , heart failure
We tested the hypothesis that brain natriuretic peptide (BNP) would decrease the effects of myocardial stunning with little effect on O 2 consumption in rabbit hearts. In two groups of anesthetized open‐chest rabbits, myocardial stunning was produced by two 15 minute occlusions of the left anterior descending (LAD) artery separated by 15 minutes of reperfusion. The treatment group had BNP (10 −3 M) topically applied to the stunned area of myocardium. Hemodynamic and functional parameters were measured. Coronary blood flow and O 2 extraction were used to determine myocardial O 2 consumption. In separate animals, we measured the function of both isolated control and simulated ischemia‐reperfusion rabbit myocytes with BNP (10 −8 ‐10 −7 M) followed by KT5823 (10 −6 M, cGMP protein kinase inhibitor). In the in vivo BNP group, baseline delay to contraction was 53±14 msec and after stunning it increased to 83±36. In the treatment group baseline delay to contraction was 44±24 and after stunning and BNP admistration it increased to 57±13. Neither stunning nor BNP administration affected regional O 2 consumption. In control myocytes, BNP (10 −7 M) decreased percent shortening (PCS) from 6.7±1.0% to 4.5±0.8%; after KT5823 administration PCS increased to 5.4±1.4%. In ischemia‐reperfusion myocytes, BNP (10 −7 M) decreased PCS from 5.0±1.1% to 3.8±0.6%; after KT5823 administration PCS did not increase (3.8±0.5%). The data illustrated that BNP administration reversed the effects of stunning and its mechanism may be independent of the cGMP protein kinase.