title: Dobutamine administration exacerbates postischaemic myocardial dysfunction in isolated rat hearts: an effect reversed by thyroxine pretreatment.
abstract: The present study has investigated the effects of dobutamine on postischaemic dysfunction in the setting of global ischaemia and reperfusion in a model of isolated heart preparation. Isolated rat hearts were subjected to 20 min of zero-flow global ischaemia followed by 45 min of reperfusion. Dobutamine administration (10 microg/kg/min) during the reperfusion period resulted in deterioration of functional recovery, which was abolished by propranolol administration. Long-term thyroxine pretreatment (12.5 microg 100 g(-1) body weight, b.i.d., s.c., for 2 weeks) reversed the detrimental effect of dobutamine and increased postischaemic recovery of function. We conclude that the combination of thyroxine pretreatment and dobutamine administration could potentially be a new therapeutic strategy to improve postischaemic dysfunction particularly in clinical settings such as cardiopulmonary bypass and/or myocardial infarction.
authors.affiliation: Department of Pharmacology, University of Athens, 75 Mikras Asias Avenue, 11527 Goudi, Athens, Greece. cpantos@cc.uoa.gr
authors.forename: Constantinos
authors.initials: C
authors.lastname: Pantos
authors.forename: Iordanis
authors.initials: I
authors.lastname: Mourouzis
authors.forename: Stylianos
authors.initials: S
authors.lastname: Tzeis
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Moraitis
authors.forename: Vassiliki
authors.initials: V
authors.lastname: Malliopoulou
authors.forename: Demosthenis D
authors.initials: DD
authors.lastname: Cokkinos
authors.forename: Hariclia
authors.initials: H
authors.lastname: Carageorgiou
authors.forename: Dennis
authors.initials: D
authors.lastname: Varonos
authors.forename: Dennis
authors.initials: D
authors.lastname: Cokkinos
mesh_terms: D000818:Animals; D002316:Cardiotonic Agents / Q000009:adverse effects / Q000494:pharmacology*; D004280:Dobutamine / Q000009:adverse effects / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects* / Q000502:physiology / Q000503:physiopathology; D006352:Heart Ventricles / Q000187:drug effects / Q000503:physiopathology; D066298:In Vitro Techniques; D017202:Myocardial Ischemia / Q000150:complications; D015428:Myocardial Reperfusion Injury / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D013974:Thyroxine / Q000494:pharmacology*; D013997:Time Factors; D016276:Ventricular Function
chemical_list: D002316:Cardiotonic Agents; D004280:Dobutamine; D011433:Propranolol; D013974:Thyroxine