Adler P S, France C, Ditto B
Department of Psychology, McGill University, Montreal, Quebec, Canada.
J Psychosom Res. 1991;35(4-5):591-7. doi: 10.1016/0022-3999(91)90053-q.
The baroreflex sensitivity of healthy young adult males who reported some history of vasovagal syncope during emotionally stressful situations (e.g. blood donation) was compared to a control group of individuals who reported no such history. The baroreflex, which induces compensatory bradycardia and vasodilation in response to acute elevations of blood pressure, was examined as a possible mechanism underlying predisposition to vasovagal reactions. Changes in heart rate and vasoconstriction in response to baroreflex stimulation (negative external cervical pressure) at rest and during administration of a mental arithmetic task and a constrictive pain stimulus were assessed. Individuals with a history of vasovagal reactions displayed greater baroreflex sensitivity during the pain stimulus and at rest, but not during mental arithmetic. These findings suggest one mechanism of risk for syncope reactions, particularly in situations involving the experience of pain.
将报告在情绪紧张情况下（如献血）有血管迷走性晕厥病史的健康年轻成年男性的压力反射敏感性，与报告无此类病史的对照组个体进行比较。压力反射会在血压急性升高时诱发代偿性心动过缓和血管舒张，该反射作为血管迷走反应易感性的潜在机制进行了研究。评估了静息状态下以及在进行心算任务和收缩性疼痛刺激时，压力反射刺激（颈部外部负压）引起的心率和血管收缩变化。有血管迷走反应病史的个体在疼痛刺激期间和静息时表现出更高的压力反射敏感性，但在心算期间没有。这些发现提示了晕厥反应的一种风险机制，尤其是在涉及疼痛体验的情况下。
