from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Of, relating to, or being the nerve fibers that supply a ganglion, especially a ganglion of the autonomic nervous system.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Describing the nerve fibres that supply a ganglion
from The Century Dictionary and Cyclopedia
- Of or pertaining to nerve-fibrillæ or other structures that are proximal with reference to a ganglion.
The cells of this column are fusiform or star-shaped, and of a medium size: the axons of some of them pass into the anterior nerve roots, by which they are carried to the sympathetic nerves: they constitute the white rami and are sympathetic or visceral efferent fibers; they are also known as preganglionic fibers of the sympathetic system; the axons of others pass into the anterior and lateral funiculi, where they become longitudinal.
The efferent sympathetic fibers which leave the central nervous system in connection with certain of the cranial and spinal nerves all end in sympathetic ganglia and are known as preganglionic fibers.
Although proof of this has so far only been obtained directly in the case of preganglionic sympathetic endings, there is, nevertheless, much to make us think that in other places as well the nerve substances are released in the nerve endings themselves.
In elegant experiments directed towards the question of the localization of the release of Ac.Ch. in the ganglion, Feldberg and Vartiainen24 were recently able to prove that it was released neither by the preganglionic fibres nor by the ganglion cells themselves, the only direct effector organ.
If, therefore, it can be proved that Ac.Ch. is formed in the "synapse", it can only, in my opinion, be in the preganglionic nerve ending or in the ganglion cell.
Gaddum23 have shown that stimulation of the preganglionic sympathetic fibres in the neck releases Ac.Ch. in the sup.cerv. ganglion, which itself stimulates the ganglion, so that progressive stimulation is set up in the postganglionic fibres.
In both cases, the phenomenon had the appearance of a direct, unbroken conduction, to ganglion cell or muscle fibre, of the same propagated wave of physico-chemical disturbance as had constituted the preganglionic or the motor nerve impulse, with only a slight, almost negligible retardation in its passage across the ganglionic synapse or the neuromuscular junction.
Even when obtained in solution this potent enzyme destroys acetylcholine with a quite remarkable rapidity; and if we could suppose it to be concentrated on surfaces at preganglionic or motor nerve endings, in immediate relation to the site of liberation and action of acetylcholine, it might furnish an adequate mechanism for the complete destruction of this substance, even during the very brief interval of the refractory period.
We have evidence, then, that both the reserve of acetylcholine, and the esterase required for its destruction, are in fact associated with the preganglionic nerve endings, as our hypothesis demands.
Feldberg and Gaddum17, though unable to reproduce effects obtained by Kibjakow with pure Locke's solution, found that, when eserine was added to the fluid perfusing the ganglion, stimulation of the preganglionic fibres regularly caused the appearance of acetycholine in the venous effluent.
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