Narcolepsy-cataplexy: deficient prepulse inhibition of blink reflex suggests pedunculopontine involvement
Narcolepsy-cataplexy: deficient prepulse inhibition of blink reflex suggests pedunculopontine involvement
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DOI：
10.1111/j.1365-2869.2012.01016.x
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发表时间：
2012-10-01
影响因子：
4.4
通讯作者：
Kofler, Markus
中科院分区：
文献类型：
--
作者：
Frauscher, Birgit;Loescher, Wolfgang N.;Kofler, Markus
下丘脑分泌素（食欲素）缺乏在发作性睡猝倒的病理生理中起重要作用。在动物模型中，向桥脚核的下丘脑分泌能投射直接参与肌张力调节，介导肌张力失调，这是中风的标志。我们假设，通过脉冲前眨眼反射抑制测试，桥脚核功能在人发作性睡猝倒中发生了改变。对20例发作性睡猝倒患者和20例健康对照者进行了桥脚核功能的神经生理学研究。测定眨眼反射、脉冲前抑制和眨眼反射兴奋性恢复情况。眨眼反射特征（R1潜伏期和幅度，R2和R2c潜伏期和曲线下面积）在两组间无显著差异（P < 0.05）。脉冲前刺激显著增加了患者和对照组的R2和R2c潜伏期，减少了R2和R2c区域。然而，患者的R2和R2c区域抑制明显低于对照组（分别为69.8 +/- 14.4和74.9 +/- 12.6%，分别为34.5 +/- 28.6和43.3 +/- 29.5%，P均< 0.001）。眨眼反射兴奋性恢复，通过配对脉冲刺激测量，不通过桥脚核介导，在患者和对照组之间没有差异（P > 0.05）。我们的数据显示，发作性睡猝倒患者的脉冲前抑制减少，而非条件眨眼反射及其兴奋性恢复正常。由于桥脚核对脉冲前抑制很重要，这些结果表明它的功能参与发作性睡猝倒。
Hypocretin (orexin) deficiency plays a major role in the pathophysiology of narcolepsycataplexy. In animal models, hypocretinergic projections to the pedunculopontine nucleus are directly involved in muscle tone regulation mediating muscle atonia a hallmark of cataplexy. We hypothesized that pedunculopontine nucleus function, tested with prepulse inhibition of the blink reflex, is altered in human narcolepsycataplexy. Twenty patients with narcolepsycataplexy and 20 healthy controls underwent a neurophysiological study of pedunculopontine nucleus function. Blink reflex, prepulse inhibition of the blink reflex and blink reflex excitability recovery were measured. Blink reflex characteristics (R1 latency and amplitude, and R2 and R2c latency and area under the curve) did not differ between patients and controls (P > 0.05). Prepulse stimulation significantly increased R2 and R2c latencies and reduced R2 and R2c areas in patients and controls. However, the R2 and R2c area suppression was significantly less in patients than in controls (to 69.8 +/- 14.4 and 74.9 +/- 12.6%, respectively, versus 34.5 +/- 28.6 and 43.3 +/- 29.5%, respectively; each P < 0.001). Blink reflex excitability recovery, as measured by paired-pulse stimulation, which is not mediated via the pedunculopontine nucleus, did not differ between patients and controls (P > 0.05). Our data showed that prepulse inhibition is reduced in narcolepsycataplexy, whereas unconditioned blink reflex and its excitability recovery are normal. Because the pedunculopontine nucleus is important for prepulse inhibition, these results suggest its functional involvement in narcolepsycataplexy.