The purpose of this protocol is to provide a mechanism f

手术室或重症监护室的患者经常需要药物来改善心脏的泵送能力和循环功能。用于这些目的的常用药物刺激心血管系统中的受体以实现这些结果。这些受体被称为肾上腺素能受体，有两种主要类型-α和β。α受体刺激导致动脉收缩，从而增加血压。β受体刺激增加心率和泵送力，也扩张动脉血管。手术室和重症监护室的患者也接受芬太尼等麻醉药物作为麻醉或治疗疼痛的一部分。芬太尼本身对心脏的影响很小，如果有的话，除了降低心率。虽然在科学文献中描述了这种缺乏心脏效应的情况，但没有研究调查芬太尼是否可以降低α或β肾上腺素能兴奋剂对心血管系统的影响。在这项研究中，我们已经表明，在狗，芬太尼减少异丙肾上腺素对心脏功能的有效性，主要是通过心率。我们还表明芬太尼与α和β受体之间的相互作用是由G蛋白介导的。目前正在进行研究，以确定这种相互作用的神经作用。通过敲除窦房结和通过起搏控制心率来研究心率作用的其他研究也在研究中。进一步了解麻醉剂是否与心脏内的心脏刺激药物相互作用，可以更好地管理手术室或重症监护室中的休克或心脏病患者，从而改善结果并可能挽救生命。

Patients in the operating room or intensive care unit frequently need medications to improve the pumping ability of their hearts and their circulatory function. Commonly used medications for these purposes stimulate receptors in the cardiovascular system to achieve these results. These receptors are known as adrenergic receptors and have two major types - alpha and beta. Alpha receptor stimulation causes arteries to constrict and thereby increases blood pressure. Beta receptor stimulation increases heart rate and pumping force and also dilates arterial blood vessels. Patients in the operating room and intensive care unit also receive narcotic medications like fentanyl as part of their anesthesia or for the treatment of pain. Fentanyl by itself has very little, if any, depressant effect on the heart except to decrease the heart rate. While this lack of cardiac effects has been described in the scientific literature, no studies have investigated whether fentanyl could decrease the effect of alpha- or beta-adrenergic stimulants on the cardiovascular system. In this study, we have shown in dogs that fentanyl diminishes the effectiveness of isoproterenol on cardiac function primarily through heart rate. We have also shown that the interaction between fentanyl and alpha and beta receptors are mediated by G-proteins. Studies are presently being performed to determine the neural role of this interaction. Additional studies investigating the role of heart rate by knocking out the sino-atrial node and controlling heart rate via pacing is also being investigated. Further understanding whether narcotics interact with cardiac stimulatory drugs within the heart could lead to better management of patients with shock or cardiac disease in the operating room or intensive care unit, and thereby improve outcome and potentially save lives.