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Updated: Oct 19, 2026

Semi-Minimal Invasive Method to Induce Myocardial Infarction in Rats and the Assessment of Cardiac Function by an Isolated Working Heart System
08:01

Semi-Minimal Invasive Method to Induce Myocardial Infarction in Rats and the Assessment of Cardiac Function by an Isolated Working Heart System

Published on: June 11, 2020

Histamine H3-receptor stimulation is unable to modulate noradrenaline release by the isolated rat heart during

C Mazenot1, A Durand, C Ribuot

  • 1Laboratoire de Pharmacologie Cardiovasculaire Expérimentale-Biomolécules, Université Joseph Fourier, Grenoble, France.

Fundamental & Clinical Pharmacology
|August 24, 1999
PubMed

The aim of this study was to evaluate the ability of H3-histaminergic prejunctional receptors to modulate the noradrenaline release induced by myocardial ischaemia in the rat, and the effects of an eventual modulation on haemodynamic, biochemical and electrophysiological parameters. Isolated rat hearts were perfused according to the Langendorff technique. Control hearts (n = 13) were not treated; two groups were treated with the H3-agonist R-alpha-methyl-histamine at 0.3 microM (n = 14) and 1 microM (n = 11) and one group, used as positive control, was treated with the selective alpha 2-agonist Mivazerol at 0.5 microM (n = 14) added to the perfusion medium. Noradrenaline, lactate and transaminase output in the coronary effluent, as well as various haemodynamic and electrophysiological parameters, were measured during global and total ischaemia (30 min) and reperfusion (30 min). alpha 2-receptor stimulation increased ischaemia-induced noradrenaline release during reperfusion (195 +/- 13 vs. 145 +/- 12 pmol.g-1 in control group, P < 0.05). In contrast, R-alpha-methyl-histamine, at both doses, did not significantly modify these parameters. Both treatments did not affect ischaemia- and reperfusion-induced haemodynamic (decrease in heart rate or in left ventricular developed pressure), biochemical (lactate and GOT release) and electrophysiological (arrhythmias or increase in action potential duration) alterations. Unlike other species, the rat appears to be insensitive to H3-histaminergic receptor modulation of ischaemia-induced noradrenaline release, although a modulation can be seen with other prejunctional receptor agonists.

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