Cerebrovascular relaxation responses to endothelium-dependent and -independent vasodilators after normothermic and hypothermic cardiopulmonary bypass in the rabbit
| Autor: | Gilbert Aldape, Bradley J. Hindman, James N. Bates, Franklin Dexter, Johann Cutkomp, Tom Smith, Sakae Enomoto |
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| Rok vydání: | 1998 |
| Předmět: |
Nitroprusside
Endothelium Muscle Relaxation Vasodilator Agents Aorta Thoracic In Vitro Techniques Muscle Smooth Vascular law.invention Animal data Phenylephrine law medicine.artery medicine Basilar artery Cardiopulmonary bypass Thoracic aorta Animals Endothelial dysfunction Aorta Cardiopulmonary Bypass business.industry Hyperthermia Induced Hypothermia medicine.disease Acetylcholine Anesthesiology and Pain Medicine medicine.anatomical_structure Anesthesia Basilar Artery Endothelium Vascular Rabbits medicine.symptom business |
| Zdroj: | Anesthesiology. 88(6) |
| ISSN: | 0003-3022 |
| Popis: | Background Cardiopulmonary bypass causes activation of leukocytes and increased concentrations of proinflammatory mediators, which may result in endothelial dysfunction. Because hypothermia attenuates many inflammatory processes, the authors hypothesized that hypothermic cardiopulmonary bypass would be associated with better endothelial function than normothermic cardiopulmonary bypass. Methods Isoflurane-anesthetized New Zealand White rabbits were randomized to undergo 90 min of either normothermic (37 degrees C, n=9) or hypothermic (27 degrees C, n=9) cardiopulmonary bypass with terminal rewarming. A third group served as anesthetized normothermic non-cardiopulmonary bypass surgical controls (n=8). Basilar artery and descending thoracic aorta were isolated from each animal. In vitro vessel relaxation responses to increasing concentrations of acetylcholine (which induces endothelial release of nitric oxide) and nitroprusside (which provides exogenous nitric oxide) were measured in phenylephrine-precontracted vessel rings. Results There were no differences in vessel relaxation responses between normothermic and hypothermic cardiopulmonary bypass groups in basilar artery or aorta. In contrast, basilar arteries from non-cardiopulmonary bypass controls had increased relaxation responses to both acetylcholine (P=0.004) and nitroprusside (P=0.031) compared with the pooled cardiopulmonary bypass animal data. Conclusions The authors observed no differences in endothelial or vascular smooth muscle function between normothermic and hypothermic cardiopulmonary bypass groups. Compared with non-cardiopulmonary bypass controls, cardiopulmonary bypass appeared to decrease basilar artery smooth muscle relaxation in response to endogenous and exogenous nitric oxide. |
| Databáze: | OpenAIRE |
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