VASOCONSTRICTION DURING COLD PRESSOR TEST--ALPHA ADRENERGIC BLOCKADE

自研究开始以来的过去三年里，我们已经完成了 研究的一部分涉及阿尔法拮抗剂和对 冷加压试验。数据显示，外围设备 酚妥拉明可减弱血管收缩反应。这些结果 以前发表过(1994年)，并被收录在过去几年 GCRC报告。在这些摘录中确认了GCRC的赠款，并 文件。 这项研究的另一个目的是评估阿尔法的影响。 肾上腺素能拮抗血管运动和代谢机制 在没有冷应激的情况下保持常温。这些研究 也完成并以摘要和手稿的形式发表 形式。研究结果表明，α-受体拮抗剂会降低血管舒缩功能。 色调，增加通过皮肤的热量损失，从而导致核心更低 温度。我们还显示了它们的剂量反应 效果。 另一个令人感兴趣的领域是心率变异性。 与李·弗莱舍在国防部共事。在麻醉学方面，我们能够 描述核心低温对心率变化的影响 人类受试者的可变性。我们发现低频功率增加了 在频谱分析中对R-R间期的变异性进行分析。

Over the last 3 years since the study has begun we have completed the portion of the study addressing alpha-antagonists and the response to the cold pressor test. The data show that the peripheral vasoconstriction response is attenuated by phentolamine. These results have been previously published (in 1994) and were included in last years GCRC report. The GCRC grant was acknowledged in these abtracts and papers. The other aim in this study was to assess the effects of alpha- adrenergic antagonism on the vasomotor and metabolic mechanisms that maintain norniothermia in the absence of cold stress. These studies were also completed and were published in abstract as well as manuscript form. The findings indicate that alpha-antagonists decrease vasomotor tone, increase heat loss through the skin, which results in a lower core temperature. There is also a dose-response that we have shown for these effects. One additional area of interest was that of heart rate variability. Working with Lee Fleisher in the Dept. of Anesthesiology, we were able to describe the effects of core hypothermia on changes in heart rate variability in human subjects. We showed increased low frequency power in the spectral analysis for R to R interval variability.