Chronic hypoxia-induced morphological and neurochemical changes in the carotid body.
Chronic hypoxia-induced morphological and neurochemical changes in the carotid body.
复制标题
慢性缺氧引起颈动脉体形态和神经化学变化。
DOI：
10.1002/jemt.10191
复制
发表时间：
2002
影响因子：
2.5
通讯作者：
Bisgard,GeraldE
中科院分区：
文献类型：
--
作者：
Wang,Zun-Yi;Bisgard,GeraldE
颈动脉体（CB）在通气控制中起重要作用。CB中的I型细胞被认为是化学感受元件，其检测动脉血中的PO 2、PCO 2和[H+]水平。这些细胞起源于神经嵴，似乎保留了一些神经元的特性。它们是易兴奋的，并产生许多神经化学物质。这些神经化学物质中的一些，如多巴胺和去甲肾上腺素，被认为主要抑制CB功能，而其他的，如三磷酸腺苷，乙酰胆碱和内皮素，被认为主要是兴奋性的。慢性缺氧（CH）诱导CB的深刻的形态学以及神经化学变化。CH使CB体积增大，并引起I型细胞肥大和有丝分裂。此外，CH改变CB的血管结构，包括诱导显著的血管舒张和新血管的生长。此外，CH上调CB内的某些神经化学系统，例如，酪氨酸羟化酶和多巴胺能活性。还有证据表明CH诱导CB神经支配内的神经化学变化，例如，一氧化氮合酶在CH期间，CB化学感受器对缺氧的敏感性增加，但许多CH诱导的结构和神经化学变化影响CB对缺氧的敏感性的机制仍有待建立。Microsc. Res. Tech. 59：168-177，2002.© 2002 Wiley利斯公司
The carotid body (CB) plays an important role in the control of ventilation. Type I cells in CB are considered to be the chemoreceptive element which detects the levels of PO2, PCO2, and [H+] in the arterial blood. These cells originate from the neural crest and appear to retain some neuronal properties. They are excitable and produce a number of neurochemicals. Some of these neurochemicals, such as dopamine and norepinephrine, are considered to be primarily inhibitory to CB function and others, such as adenosine triphosphate, acetylcholine, and endothelin, are thought to be primarily excitatory. Chronic hypoxia (CH) induces profound morphological as well as neurochemical changes in the CB. CH enlarges the size of CB and causes hypertrophy and mitosis of type I cells. Also, CH changes the vascular structure of CB, including inducing marked vasodilation and the growth of new blood vessels. Moreover, CH upregulates certain neurochemical systems within the CB, e.g., tyrosine hydroxylase and dopaminergic activity in type I cells. There is also evidence that CH induces neurochemical changes within the innervation of the CB, e.g., nitric oxide synthase. During CH the sensitivity of the CB chemoreceptors to hypoxia is increased but the mechanisms by which the many CH‐induced structural and neurochemical changes affect the sensitivity of CB to hypoxia remains to be established. Microsc. Res. Tech. 59:168–177, 2002. © 2002 Wiley‐Liss, Inc.