Lagerweij E, Nelis P C, Wiegant V M, van Ree J M
Science. 1984 Sep 14;225(4667):1172-4. doi: 10.1126/science.6089344.
The twitch procedure in horses attenuates the increase in the heart rate evoked by pain-inducing stimuli and the reaction of the animals to such stimuli. Endorphin systems are probably involved in the effectiveness of the twitch, since its action is blocked by naloxone and its application increases plasma concentrations of immunoreactive beta-endorphin. The mode of action of the twitch cannot be explained by the generally accepted theory of divertive pain and may resemble that of classical acupuncture.
马匹的轻拍操作可减弱由致痛刺激引起的心率增加以及动物对这类刺激的反应。内啡肽系统可能参与了轻拍操作的有效性，因为其作用可被纳洛酮阻断，且应用轻拍操作会增加血浆中免疫反应性β-内啡肽的浓度。轻拍操作的作用方式无法用普遍接受的分散性疼痛理论来解释，可能类似于传统针灸的作用方式。
