猫脊髓背角双投射神经元的外周传入特性

电刺激猫颈髓背索和背外侧索可双重地逆向激动同侧腰骶髓背角神经元。该神经元对非伤害性和伤害性皮肤刺激发生反应;对电刺激其感受野的反应具有单突触性、低阈值和传导快等特征;该神经元的突触前和突触后纤维的传导速度相似,但不具正变关系。结果表明,SCT-DCPS神经元具有低阈机械感受型和广动力范围型两种生理学模型;从A_β传人接受输入并与之构成单突触联系;其突触前纤维直径与突触后纤维直径之间不具匹配关系。

PERIPHERAL AFFERENT PROPERTIES OF DUAL PROJECTION NEURONS FROM THE DORSAL SPINAL HORN IN CATS

Neurons in the lumbosacral dorsal horn were doubly activated by antidromic sti-mualtion of both the ipsilateral dorsal and dorsolateral funiculi in the cervical spiual cord. These neurons respionded to innocuous and noxious stimuli delivered to skin. Their responses to electrical stimulation, of receptive fields were characterized by monos-ynaptic linleage, low threshold and fastness in condition velocity. No correlation between the neurons pre- and post-synaptic fibers were shown although they were similar in size. The results indicate that there are two classes of dual projection neurons, low threshold mechanoreceptive, and wide dynamic range; the neurons receive input from and form monosynaptic connection with A beta afferent fibers and there is no matching between the per- and postsynaptic fibers of the neurons.