Comparative anatomy of the accessory ciliary ganglion in mammals

Abstract

The orbits of 13 mammalian species (pig, sika deer, domestic sheep, horse, cat, fox, racoon dog, marten, rat, rabbit, crab-eating macaque, japanese macaque and man) were stained with silver nitrate and dissected under a dissecting microscope with special attention to the presence and location of the accessory ciliary ganglion. Some preparations were stained with thionin and examined as whole-mounts in a transmission microscope. The accessory ciliary ganglion was present in all 13 species, although the number and degree of development varied greatly from species to species. The accessory ciliary ganglion could be readily differentiated from the main ciliary ganglion in the following respects: it was located on the short ciliary nerve, and it had no root derived directly from the inferior trunk of the oculomotor nerve and it never attaches to this nerve. In many species, ganglion cells were also scattered in the short ciliary nerves in the stained whole preparations. In a few species, there were one or more small ganglia on the nerve to the inferior oblique muscle.

Axosomatic synapses of the rat ciliary ganglion

“…The principal ciliary ganglion is composed of a small number (77-200) of parasympathetic postganglionic neurons (Kuwayama et al, 1987;Landis et al, 1987;Marfurt and Ellis, 1993;Wigston, 19831, with an equivalent number situated in scattered accessory ganglia (Kuchiiwa et al, 1989;Kuwayama et al, 1987). Each cell receives only two preganglionic inputs on average (range, 1 4 ) and the large majority (>go%) innervate structures of the anterior eye (Wigston, 19831, princi-pally the iris and the ciliary body (Huhtala et al, 1976;Marfurt and Ellis, 1993).…”

Parasympathetic Innervation of the Rat Cornea

“…It is generally assumed that the cornea is not supplied by parasympathetic nerves ; however, a careful review of the literature reveals a growing body of evidence that may support their existence. Extirpation of the rat main ciliary ganglion, a surgical procedure that selectively destroys parasympathetic neurons without damaging neighboring sensory and sympathetic fibers (Kuwayama et al, 1987 ;Kuchiiwa, Kuchiiwa and Suzuki, 1989), causes degeneration of small numbers of corneal axons (Tervo et al, 1979). Surgical transection of rat ocular sensory and sympathetic nerves significantly reduces, but does not totally eliminate, corneal nerve fibers stained immunohistochemically against acetylcholinesterase, tyrosine hydroxylase, and certain neuropeptides (Tervo, 1976 ;Marfurt and Ellis, 1993 ;Jones and Marfurt, 1998).…”

Morphometric Analysis of the Ciliary Ganglion in the Domestic Turkey (Meleagris Gallopavo F. Domestica) and Domestic Duck (Anas Platyrhynchos F. Domestica)

“…However, in many species, e.g. cat, horse, sheep, goat, boar, pig, fox, Egiptian spiny mouse, and even human, accessory ganglia were found aside from the main ciliary ganglia (8,10,17,21). In mammals, the ciliary ganglion cells reveal great differentiation of the diameter among species, e.g.…”