Interaction between opioid receptor and adrenoceptor signaling in ischemia reperfusion of the isolated rat heart / 浙江大学学报·医学版

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the interaction between opioid receptor (OR) stimulation and adrenergic receptor (AR) stimulation in the isolated ischaemia/reperfusion (I-R) rat heart.</p><p><b>METHODS</b>Male Sprague-Dawley rats were used for Langendoff isolated heart perfusion. Myocardial ischemia for 20 min was followed by 30 min of reperfusion, during which the kappa-OR agonist U50488h and beta(1)-AR agonist norepinephrine (NE) were administered.</p><p><b>RESULTS</b>(1) 50488h antagonized the effect of NE in rising left ventricular systolic pressure (LVSP) in the early phase of myocardial ischemia at 10, 20, 30 min of reperfusion. (2) Arrhythmia scores in the I-R+NE+U50488h group were markedly lower than those in the I-R group during the 10 - 20 min reperfusion period. No significant differences in arrhythmia scores were found in either I-R+U50488h or I-R+NE group when compared with I-R group. (3) Compared with the I-R group, U50488h alone or plus NE decreased reperfusion heart rates after myocardial ischemia while NE alone showed no effect.</p><p><b>CONCLUSION</b>It is suggested that the interaction in the signaling pathway between kappa-OR and beta(1)-AR occurred during myocardial I-R of rat heart.</p>