Cortical influences on the vestibular nuclei of the cat.
Cortical influences on the vestibular nuclei of the cat.
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皮质对猫前庭核的影响。
DOI：
10.1007/s002210050651
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发表时间：
1999
影响因子：
2
通讯作者：
Umezaki,T
中科院分区：
文献类型：
--
作者：
Wilson,VJ;Zarzecki,P;Schor,RH;Isu,N;Rose,PK;Sato,H;Thomson,DB;Umezaki,T
我们的目标是研究猫前庭反射皮质调节的潜在底物。在最初的实验中，将小麦胚芽凝集辣根过氧化物酶注射到 Deiters 核和头端降核中，发现皮质区域 6、2 和 3a 存在双侧逆行填充神经元集落（每个集落约 60 个细胞）。在用氯醛糖-氨基甲酸酯麻醉的猫中，我们用脉冲串刺激区域 2 和 3a，同时记录同侧前庭核神经元，其特征在于它们对正弦倾斜的反应，并测试了对上颈髓刺激是否存在逆向反应。大多数神经元受到皮质刺激的影响，表现出促进、抑制或两者的混合。区域 2 的刺激比区域 3a 的刺激更有效。尽管在解剖学上存在直接皮质前庭投射，但促进和抑制的特性表明两者都是由多突触通路引起的。皮质效应广泛分布于前庭神经元，而不考虑这些神经元对正弦倾斜的反应。对外侧和内侧前庭脊髓束神经元的影响没有显着差异，但作为一个群体，前庭脊髓神经元比未从 C2 段逆向激活的神经元更容易受到皮质刺激的影响。我们的结论是，通过对前庭脊髓神经元的影响，皮质区域 2 和 3a 的神经元应该能够调节行为动物中作用于颈部和四肢的前庭反射。
Our goal was to study potential substrates for cortical modulation of vestibular reflexes in the cat. In initial experiments, injections of wheat-germ-agglutinate-horseradish-peroxidase into Deiters’ nucleus and the rostral descending nucleus revealed bilateral colonies of retrogradely filled neurons in cortical areas 6, 2, and 3a (about 60 cells per colony). In cats anesthetized with chloralose-urethane, we stimulated areas 2 and 3a with trains of pulses while recording from ipsilateral vestibular-nucleus neurons, which were characterized by their responses to sinusoidal tilts and tested for the presence of antidromic responses to stimulation of the upper cervical cord. A majority of the neurons was affected by cortical stimulation, showing either facilitation, inhibition, or a mixture of the two. Stimulation in area 2 was more effective than stimulation in area 3a. Despite the anatomic presence of direct cortico-vestibular projections, properties of facilitation and inhibition suggest that both were evoked by polysynaptic pathways. Cortical effects were broadly distributed to vestibular neurons without regard to responses of these neurons to sinusoidal tilts. There was no significant difference between effects on lateral and medial vestibulospinal tract neurons, but, as a group, vestibulospinal neurons were much more likely to be affected by cortical stimulation than neurons not antidromically activated from the C2 segment. We conclude that, by their influence on vestibulospinal neurons, neurons in cortical areas 2 and 3a should be able to modulate, in behaving animals, vestibular reflexes acting on the neck and limbs.