Tijssen M A, Padberg G W, van Dijk J G
Department of Neurology, Leiden University Hospital, The Netherlands.
Arch Neurol. 1996 Jul;53(7):608-13. doi: 10.1001/archneur.1996.00550070046011.
The major and minor forms of hereditary hyperekplexia (HE) are characterized by excessive startle responses, which are accompanied by transient stiffness only in major HE; patients with major HE also have continuous stiffness during infancy. A point mutation has been identified for major HE in the gene encoding the alpha 1 subunit of the glycine receptor but not for minor HE.
To measure startle reflexes and autonomic responses in the major and minor forms of HE in the original Dutch HE pedigree.
Startle reflexes and autonomic responses were studied with 3 series of 20 auditory stimuli with intervals of 10 seconds (at 90 and 113 dB) and 60 seconds (at 113 dB).
A university hospital neurologic department.
Four patients with minor and 9 patients with major HE (patient groups) (a part of the Dutch HE family pedigree) and 20 healthy controls (control group).
Startle movements were quantified with latencies and areas of electromyographic bursts of the following 4 muscles: the orbicular muscle of the eye, the sternocleidomastoid muscle, the biceps muscle of the arm, and thenar muscles. Autonomic reactions were measured with psychogalvanic responses. RESULTS. The 4 muscles contracted in similar order in the groups. The onset latencies of the orbicular muscle of the eye, the sternocleidomastoid muscle, and the biceps muscle of the arm were significantly prolonged in patients with minor HE (P < .006). The frequencies of occurrence of the electromyographic bursts were not different in the minor HE and major HE groups, but they were significantly higher in both patient groups compared with those in the control group (P < .001). The magnitude of the startle responses did not differ between the 2 patient groups (P = .4), but it was larger in both patient groups than in the control group (P < .001). Startle habituation in the minor HE group was much weaker than in the major HE group (P < .001) or in the control group (P < .001). The size of psychogalvanic responses (P = .1) and the degree of habituation (P = .24) in the minor HE group did not differ from those in the major HE group. Compared with that in the control group, the size of psychogalvanic responses in the minor HE group was larger (P < .001) and they habituated stronger (P < .001).
The differences in the startle pattern between major HE and minor HE agree with the clinical and genetic findings: only major HE constitutes part of the HE phenotype. The cause of the minor HE is, as yet, unknown.
遗传性惊吓症（HE）的主要和次要形式的特征是惊吓反应过度，其中只有主要型HE伴有短暂性僵硬；主要型HE患者在婴儿期还存在持续性僵硬。已在编码甘氨酸受体α1亚基的基因中发现了主要型HE的一个点突变，但次要型HE未发现。
测量原始荷兰HE家系中主要和次要型HE患者的惊吓反射和自主反应。
通过3组20次听觉刺激研究惊吓反射和自主反应，刺激间隔分别为10秒（90分贝和113分贝）和60秒（113分贝）。
一家大学医院的神经科。
4例次要型HE患者和9例主要型HE患者（患者组）（荷兰HE家族谱系的一部分）以及20名健康对照者（对照组）。
通过以下4块肌肉的肌电图爆发潜伏期和面积对惊吓动作进行量化：眼轮匝肌、胸锁乳突肌、肱二头肌和鱼际肌。通过皮肤电反应测量自主反应。结果。各组中4块肌肉的收缩顺序相似。次要型HE患者的眼轮匝肌、胸锁乳突肌和肱二头肌的起始潜伏期显著延长（P < .006）。次要型HE组和主要型HE组的肌电图爆发发生频率无差异，但与对照组相比，两个患者组的频率均显著更高（P < .001）。两个患者组之间的惊吓反应幅度无差异（P = .4），但两个患者组的反应幅度均大于对照组（P < .001）。次要型HE组的惊吓习惯化比主要型HE组（P < .001）或对照组（P < .00）弱得多。次要型HE组的皮肤电反应大小（P = .1）和习惯化程度（P = .24）与主要型HE组无差异。与对照组相比，次要型HE组的皮肤电反应大小更大（P < .001），且习惯化更强（P < .00）。
主要型HE和次要型HE在惊吓模式上的差异与临床和遗传学发现一致：只有主要型HE构成HE表型的一部分。次要型HE的病因尚不清楚。
