Picture of wind turbine against blue sky

Open Access research with a real impact...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs.

The Energy Systems Research Unit (ESRU) within Strathclyde's Department of Mechanical and Aerospace Engineering is producing Open Access research that can help society deploy and optimise renewable energy systems, such as wind turbine technology.

Explore wind turbine research in Strathprints

Explore all of Strathclyde's Open Access research content

Adrenomedullin acts via nitric oxide and peroxynitrite to protect against myocardial ischaemia-induced arrhythmias in anaesthetized rats

Looi, Y.H. and Kane, K.A. and McPhaden, A.R. and Wainwright, C.L. (2006) Adrenomedullin acts via nitric oxide and peroxynitrite to protect against myocardial ischaemia-induced arrhythmias in anaesthetized rats. British Journal of Pharmacology, 148. pp. 599-609. ISSN 0007-1188

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

1The overall aim of this study was to determine if adrenomedullin (AM) protects against myocardial ischaemia (MI)-induced arrhythmias via nitric oxide (NO) and peroxynitrite.2In sham-operated rats, the effects of in vivo administration of a bolus dose of AM (1 nmol kg−1) was assessed on arterial blood pressure (BP), ex vivo leukocyte reactive oxygen species generation and nitrotyrosine deposition (a marker for peroxynitrite formation) in the coronary endothelium.3In pentobarbitone-anaesthetized rats subjected to ligation of the left main coronary artery for 30 min, the effects of a bolus dose of AM (1 nmol kg−1, i.v.; n=19) or saline (n=18) given 5 min pre-occlusion were assessed on the number and incidence of cardiac arrhythmias. In a further series of experiments, some animals received infusions of the NO synthase inhibitor N(G)-nitro-L-arginine (LNNA) (0.5 mg kg−1 min−1) or the peroxynitrite scavenger N-mercaptopropionyl-glycine (MPG) (20 mg kg−1 h−1) before AM.4AM treatment significantly reduced mean arterial blood pressure (MABP) and increased ex vivo chemiluminescence (CL) generation from leukocytes in sham-operated animals. AM also enhanced the staining for nitrotyrosine in the endothelium of coronary arteries.5AM significantly reduced the number of total ventricular ectopic beats that occurred during ischaemia (from 1185±101 to 520±74; P<0.05) and the incidences of ventricular fibrillation (from 61 to 26%; P<0.05). AM also induced a significant fall in MABP prior to occlusion. AM-induced cardioprotection was abrogated in animals treated with the NO synthase inhibitor LNNA and the peroxynitrite scavenger MPG.6This study has shown that AM exhibits an antiarrhythmic effect through a mechanism that may involve generation of NO and peroxynitrite.