Amplification by phenylephrine and serotonin of coronary vasoconstriction induced by a high arterial blood oxygen tension
| Autor: | Michel Duvelleroy, Olivier Charansonney, Stéphane Mouren, Eric Vicaut |
|---|---|
| Rok vydání: | 1994 |
| Předmět: |
Male
Serotonin medicine.medical_specialty Swine Physiology Hemodynamics Hyperoxia Phenylephrine Physiology (medical) Internal medicine medicine Animals business.industry Blood flow Coronary Vessels Stimulation Chemical respiratory tract diseases Oxygen tension Perfusion Endocrinology Equipment and Supplies Vasoconstriction Anesthesia Circulatory system Arterial blood Rabbits Cardiology and Cardiovascular Medicine business medicine.drug |
| Zdroj: | Cardiovascular Research. 28:1326-1330 |
| ISSN: | 0008-6363 |
| Popis: | The aim was to investigate the effect on the coronary network of the interaction between high arterial blood oxygen tension (PaO2) and stimulation by the alpha adrenergic agonist phenylephrine or by serotonin in an isolated, blood perfused rabbit heart preparation.Fresh pig erythrocytes in Krebs-Henseleit buffer were oxygenated to reach normal PaO2 [19.4(SEM 0.7) kPa] or high PaO2 [53.2(5.5) kPa]. Blood oxygen content was kept constant despite the higher PaO2, by slightly reducing the haemoglobin concentration from 9.3(0.2) to 8.8(0.2) g.100 ml-1 (p0.01). Coronary blood flow was kept constant throughout the study, so that the oxygen supply would not vary with the rise in PaO2. Increases in coronary resistance were therefore reflected by increased perfusion pressure.Switching from normal to high PaO2 induced coronary vasoconstriction, reflected by enhanced perfusion pressure of +21(5)%. After pretreatment with the alpha adrenergic agonist phenylephrine, perfusion of a high PaO2 solution increased coronary resistance by +35(7)% (p0.05), a value significantly higher than that found without phenylephrine. Oxygen consumption and myocardial performance did not vary throughout the study. To determine whether this amplification of the response was specifically due to alpha agonist stimulation or could be observed with other vasoactive agents, we applied the same protocol using serotonin instead of phenylephrine. Here again, coronary vasoconstriction rose in response to high PaO2 after serotonin infusion [+25(5)% versus +59(10)%].The response of the coronary network to high PaO2 is amplified by pretreatment with the alpha adrenergic agonist phenylephrine or with serotonin, regardless of any changes in metabolic status. |
| Databáze: | OpenAIRE |
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