Angaut-Petit D
Exp Brain Res. 1975 May 22;22(5):471-93. doi: 10.1007/BF00237349.
Microelectrode recordings were made from dorsal column postsynaptic (DCPS) fibres, in the fasciculus gracilis of the cat, at thoracic level Th 12, and from single cells in the nucleus gracilis. The sensitivity of the fibres (Th 12) and cells (bulbar level) to both gentle and noxious stimuli was studied and a classification of the units was made on the basis of their responses to these natural stimuli. The DCPS fibres have been classified into three groups: i) 16.3% of them were activated only by light mechanical stimuli, ii) a few responded to nothing but noxious mechanical stimuli, iii) 77% were characterized by their sensitivity to both gentle and noxious stimuli and constituted the polymodal group. The study of the nucleus gracilis cells revealed that 31.2% of the total number of cells investigated in the nucleus were also characterized by a high degree of modality convergence (polymodal cells). Besides their convergence, the polymodal DCPS fibres and the polymodal cells of the nucleus gracilis were functionally in contrast to the properties of the specific fibres and cells of the dorsal column system in other respects: i) they responded with a slowly adapting response to constant mechanical stimulation of the skin, ii) they were sensitive to noxious mechanical and thermal stimuli. It is argued that the polymodal cells could be the bulbar relay of the impulses conveyed through the DCPS fibres of the fasciculus gracilis. The possible role of the dorsal column system in nociception is discussed in the light of the results.
在猫的第12胸段，从薄束中的背柱突触后（DCPS）纤维以及薄束核中的单个细胞进行微电极记录。研究了纤维（第12胸段）和细胞（延髓水平）对轻柔刺激和伤害性刺激的敏感性，并根据它们对这些自然刺激的反应对这些单位进行了分类。DCPS纤维已被分为三组：i）其中16.3%仅由轻度机械刺激激活；ii）少数仅对伤害性机械刺激有反应；iii）77%的特征是对轻柔刺激和伤害性刺激均敏感，构成多模式组。对薄束核细胞的研究表明，在薄束核中所研究的细胞总数的31.2%也具有高度的模式汇聚特征（多模式细胞）。除了它们的汇聚性之外，多模式DCPS纤维和薄束核的多模式细胞在功能上在其他方面与背柱系统的特定纤维和细胞的特性形成对比：i）它们对皮肤的持续机械刺激以缓慢适应性反应做出反应；ii）它们对伤害性机械和热刺激敏感。有人认为，多模式细胞可能是通过薄束的DCPS纤维传递的冲动的延髓中继站。根据这些结果讨论了背柱系统在伤害感受中的可能作用。
