Medina L, Smeets W J
Departamento de Biologia Celular, Facultad de Biologia, Universidad de La Laguna, Tenerife, Spain.
J Comp Neurol. 1991 Jun 22;308(4):614-29. doi: 10.1002/cne.903080408.
To determine how the basal ganglia in reptiles may influence visuomotor behavior, the connections from the basal ganglia to the tectum of the midbrain were studied in several species of reptiles. Immunohistochemical studies by means of antibodies against Leu-enkephalin (LENK) as well as experimental hodological studies with anterograde (PHA-L) and retrograde (HRP, Fluorogold, Cholera toxin) tracers were carried out. The results indicate that within the class of Reptilia, two different patterns occur: one in which information from the basal ganglia is relayed to the tectum via the substantia nigra as well as via a pretectal, enkephalinergic cell group, and another one in which only the ventral route, via the substantia nigra, is present. The former pattern is found in turtles, crocodiles, and the lacertid lizards Podarcis and Gallotia, and the latter pattern in the gekkonid lizards Gekko and Eublepharis, in Varanus, and in the snakes Python and Thamnophis. The presence or absence of the pretectal relay center is reflected in the laminar distribution of LENK immunoreactivity in the tectum. The apparent lack of a pretectal relay in nocturnal gekkonids and in snakes underlines the hypothesis (Reiner et al., '84: T.I.N.S. 7:320-325) that a de-emphasis of visual-basal ganglia mechanisms has occurred during the evolution of ancestral reptiles to modern mammals.
为了确定爬行动物的基底神经节如何影响视觉运动行为，研究人员在几种爬行动物中研究了从基底神经节到中脑顶盖的连接。采用抗亮氨酸脑啡肽（LENK）抗体进行免疫组织化学研究，并使用顺行示踪剂（PHA-L）和逆行示踪剂（HRP、荧光金、霍乱毒素）进行实验性示踪研究。结果表明，在爬行纲中出现了两种不同的模式：一种模式是基底神经节的信息通过黑质以及一个顶盖前脑啡肽能细胞群传递到顶盖；另一种模式是仅存在通过黑质的腹侧途径。前一种模式见于龟、鳄鱼以及蜥蜴科蜥蜴波氏蜥蜴和加那利蜥蜴，后一种模式见于壁虎科蜥蜴壁虎和睑虎、巨蜥，以及蛇类蟒蛇和束带蛇。顶盖前中继中心的有无反映在顶盖中LENK免疫反应性的层状分布上。夜行性壁虎和蛇类明显缺乏顶盖前中继，这强化了一种假说（赖纳等人，1984年：《神经科学趋势》7：320 - 325），即在从原始爬行动物到现代哺乳动物的进化过程中，视觉 -基底神经节机制的重要性有所降低。
