The central effect of TRH is transmitted mainly via cholinergic fibers in the vagus. Sympatheticfibers are also involved.
TRH中枢效应的传出途径以迷走胆碱能纤维为主，交感神经可能亦有一定的作用。
2
Under normal conditions some catecholaminergic fibers innervate primary afferent neurons and there is no significant functional communication between sympatheticfibers and sensory neurons.
The distribution of afferent fibers and terminals in the sympathetic ganglion and the cardiac wall of the cat were studied with autoradiographic technique.