Coronary vasomotor disorders during hypoxia-reoxygenation: Do calcium channel blockers play a protective role?
| Autor: | M. F. Prieto Rodriguez, A. Ordoñez Fernández, J. Muñoz García, M. M. Viloria Peñas, J.M. Borrego Domínguez, A. Hernández Fernández, E. Gutiérrez Carretero |
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| Předmět: |
medicine.medical_specialty
Nifedipine Swine Coronary Vasospasm Vasodilation Myocardial Reperfusion Myocardial Reperfusion Injury In Vitro Techniques Muscle Smooth Vascular Coronary circulation Internal medicine Coronary Circulation Medicine Animals Hypoxia Vasomotor business.industry Extracorporeal circulation General Medicine Hypoxia (medical) medicine.disease Calcium Channel Blockers Coronary Vessels Adenosine Diphosphate medicine.anatomical_structure Vasoconstriction Coronary vasospasm Cardiology Endothelium Vascular medicine.symptom business medicine.drug |
| Zdroj: | Scopus-Elsevier |
| Popis: | During heart surgery, myocardial dysfunction may occasionally appear when extracorporeal circulation is discontinued, causing serious haemodynamic disorders. Many mechanisms are involved in this hypoxia-reoxygenation syndrome. The aim of this experimental study was to characterize the vasomotor disorders that take place in the isolated porcine coronary artery during in vitro hypoxia-reoxygenation and to analyse the effect of nifedipine on them. Rings of porcine coronary artery were placed in an organ chamber connected to a system that recorded isometric forces. The vascular rings were divided into two groups: control group (no nifedipine) and study group (nifedipine, 10(-6) mol/l). The vascular rings were precontracted with 30 mmol/l KCl and then hypoxia-reoxygenation was induced. Control arterial rings showed important changes in coronary vasomotor tone: severe hypoxic contraction (from 14.48+/-1.16 g of stable contraction to 17.6+/-0.44 g after the imposition of hypoxia), and transient vasodilation during reoxygenation (69.9+/-10.1% of the maximum contraction achieved). The nifedipine group experienced a slow, progressive, vasodilation throughout the whole experiment (73+/-3.5% of the maximum contraction). Neither hypoxic vasospasm nor fluctuations of the coronary vascular tone occurred. Thus, at the end of the hypoxia, the control vessels presented a degree of contraction similar to the initial level. However, in the rings treated with nifedipine, the percentage of dilation was 73+/-3.5% (P |
| Databáze: | OpenAIRE |
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