Ozawa Y, Okado N
Department of Neonatology, Toho University School of Medicine, Ohta, Tokyo, Japan.
Neuropediatrics. 2002 Jun;33(3):142-9. doi: 10.1055/s-2002-33678.
We compared the developmental changes of 5-hydroxytryptamine (5-HT) 1 A and 5-HT2 A receptor immunoreactivity in the nuclei in relation to the cardiorespiratory or autonomic function in the human brain stem in sudden infant death syndrome (SIDS) and congenital central hypoventilation syndrome (CCHS) patients and age-matched controls by means of immunohistochemical methods. There were significant decreases in 5-HT1 A and 5-HT2 A receptor immunoreactivity in the dorsal nucleus of the vagus, solitary nucleus and ventrolateral medulla in the medulla oblongata, and significant increases in the periaqueductal gray matter (PAG) of the midbrain in SIDS victims, but there were no significant differences between those in CCHS patients and controls. The decreased immunoreactivity of the receptors in the medulla oblongata was accompanied by brain stem gliosis. Therefore, the decreases in the receptors may be secondary to chronic hypoxia or repeated ischemia, but may be causally related to some impairment of the developing cardiorespiratory neuronal system. As 5-HT1 A and 5-HT2 A receptors were the most abundant in the fetal period and then decreased with subsequent development, the increases in 5-HT1 A and 5-HT2 A receptor immunoreactivity in PAG may reflect delayed neuronal maturation, but may also reflect compensatory changes in response to hypofunctioning serotonergic neurons in the medulla oblongata in SIDS. There was no abnormal expression of 5-HT1 A and 5-HT2 A receptors in CCHS brain stems, and so the pathophysiology seems to be different between SIDS and CCHS patients.
我们采用免疫组织化学方法，比较了婴儿猝死综合征（SIDS）和先天性中枢性低通气综合征（CCHS）患者以及年龄匹配的对照者脑干中与心肺或自主神经功能相关的核团中5-羟色胺（5-HT）1A和5-HT2A受体免疫反应性的发育变化。SIDS受害者延髓中迷走神经背核、孤束核和延髓腹外侧的5-HT1A和5-HT2A受体免疫反应性显著降低，中脑导水管周围灰质（PAG）显著增加，但CCHS患者与对照者之间无显著差异。延髓中受体免疫反应性降低伴有脑干胶质细胞增生。因此，受体减少可能继发于慢性缺氧或反复缺血，但可能与发育中的心肺神经元系统的某些损伤存在因果关系。由于5-HT1A和5-HT2A受体在胎儿期最为丰富，随后随着发育而减少，PAG中5-HT1A和5-HT2A受体免疫反应性增加可能反映神经元成熟延迟，但也可能反映SIDS中延髓中血清素能神经元功能低下的代偿性变化。CCHS脑干中5-HT1A和5-HT2A受体无异常表达，因此SIDS和CCHS患者的病理生理学似乎不同。
