Phenotypic specification of hindbrain rhombomeres and the origins of rhythmic circuits in vertebrates
Phenotypic specification of hindbrain rhombomeres and the origins of rhythmic circuits in vertebrates
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DOI：
10.1159/000113351
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发表时间：
1997-01-01
影响因子：
1.7
通讯作者：
Baker, R
中科院分区：
文献类型：
--
作者：
Bass, AH;Baker, R
本文考虑了脊椎动物中产生节律行为的颅神经回路的个体发育和系统发育。这些行为的特征是由神经元网络建立的可预测时间模式，这些神经元网络分别称为起搏器、神经振荡器或中枢模式发生器。比较脊椎动物研究表明，胚胎后脑被分成称为菱形体的分段区室，每个区室产生不同的颅运动神经元补充，以及尚未识别的中间神经元群体。我们现在提出，新颖的节律回路是与原索动物-脊椎动物过渡期间心脏和呼吸泵的采用相关的创新。我们进一步认为，最近的创新的模式生成回路，例如发声、电动和眼外系统，都起源于胚胎后脑（菱形节 7-8）的相同 Hox 基因特定区室，这些区室产生了有节奏的活跃心脏和呼吸回路。最后，我们提出，源自菱形体 7 和 8 的神经元产生模式的能力是由于它们产生起搏器振荡的电反应特性，最好的代表是下橄榄，它也起源于这些相同的后脑区室，并被建议在整个脊椎动物的神经轴中建立与感觉运动功能耦合的节律性振荡。
This essay considers the ontogeny and phylogeny of the cranial neural circuitry producing rhythmic behaviors in vertebrates. These behaviors are characterized by predictable temporal patterns established by a neuronal network variously referred to as either a pacemaker, neural oscillator or central pattern generator. Comparative vertebrate studies have demonstrated that the embryonic hindbrain is divided into segmented compartments called rhombomeres, each of which gives rise to a distinct complement of cranial motoneurons and, as yet, unidentified populations of interneurons. We now propose that novel rhythmic circuits were innovations associated with the adoption of cardiac and respiratory pumps during the protochordate-vertebrate transition. We further suggest that the pattern-generating circuits of more recent innovations, such as the vocal, electromotor and extraocular systems, have originated from the same Hox gene-specified compartments of the embryonic hindbrain (rhombomeres 7-8) that gave rise to rhythmically active cardiac and respiratory circuits. Lastly, we propose that the capability for pattern generation by neurons originating from rhombomeres 7 and 8 is due to their electroresponsive properties producing pacemaker oscillations, as best typified by the inferior olive which also has origins from these same hindbrain compartments and has been suggested to establish rhythmic oscillations coupled to sensorimotor function throughout the neuraxis of vertebrates.