Kondo M, Sears T A, Sadakane K, Nisimaru N
Department of Physiology, Oita Medical University, Japan.
Neurosci Res. 1998 Feb;30(2):111-7. doi: 10.1016/s0168-0102(97)00112-0.
In decerebrate rabbits we recorded simultaneously field potentials in lobule VIIa of the vermal cerebellar cortex and the vagal compound action potentials (vCAPs) proximally in the vagus nerve following electrical stimulation distally in the same nerve at different intensities. Four principal components of the vCAP were distinguished based on their peak conduction velocities. Their velocities were component I, 67-100 m/s; II, 28-50 m/s; III, 6-28 m/s, IV, 0.4-1.3 m/s. A collision test based on stimulating the recurrent laryngeal nerve identified component I and sub-component IIa of the vCAP as being due to the motor fibres of the descending limb of the nerve. The field potentials evoked in lobule VIIa by electrical stimulation of the cervical vagus nerve were climbing fibre responses as judged by the characteristics of their lamina profile and their response to high frequency stimulation. These field potentials in lobule VIIa correlated most closely with the component III of the vCAP; particularly with a sub-component IIIa of the vagus. Based on the investigations by Evans and Murray (1954) (Histological and functional studies on the fibre composition of the vagus nerve of the rabbit. J. Anat. (Lond.) 88, 320-337) in the rabbit, and by Paintal (1963) (Vagal afferent fibres. Ergeb. Physiol. 52, 74-156) and Mei (1970) (Cardiovascular and respiratory vagal mechanoreceptors in the cat. Exp. Brain Res. 11, 480-501) in the cat, component III is most likely to be due to receptors from the heart and a part of the pulmonary stretch receptors.
在去大脑的兔中，我们在延髓小脑皮层小叶VIIa同时记录场电位，并在迷走神经远端以不同强度进行电刺激后，在迷走神经近端记录迷走复合动作电位（vCAPs）。根据vCAP的峰值传导速度区分出四个主要成分。它们的速度分别为：成分I，67 - 100 m/s；II，28 - 50 m/s；III，6 - 28 m/s；IV，0.4 - 1.3 m/s。基于刺激喉返神经的碰撞试验确定，vCAP的成分I和亚成分IIa是由该神经下行支的运动纤维引起的。通过对其层状分布特征和对高频刺激的反应判断，由颈迷走神经电刺激在小叶VIIa诱发的场电位为攀缘纤维反应。小叶VIIa中的这些场电位与vCAP的成分III最密切相关，特别是与迷走神经的亚成分IIIa。根据Evans和Murray（1954年）（兔迷走神经纤维组成的组织学和功能研究。《解剖学杂志》（伦敦）88，320 - 337）对兔的研究，以及Paintal（1963年）（迷走传入纤维。《生理学进展》52，74 - 156）和Mei（1970年）（猫的心血管和呼吸迷走机械感受器。《实验脑研究》11，480 - 501）对猫的研究，成分III最有可能是由心脏的感受器和一部分肺牵张感受器引起的。
