The termination of optic nerve fibers in the albino mouse

To establish the terminal sites of the optic nerve fibers in the albino mouse, the immunohistochemical method using cholera toxin, subunit B (CTB), as well as three kinds of selective silver impregnation methods for degenerating nerve fibers were used. Termination was confirmed in the following nuclei: bilateral dorsal nuclei of the lateral geniculate body (LGB), ventral nuclei of LGB, preoptic areas, posterolateral nuclei, superior colliculi, suprachiasmatic nuclei, medial terminal nuclei of the accessory optic tract (AOT), and dorsal terminal nuclei of AOT. The percentage of the optic nerve fibers crossing at the optic chiasm was estimated at 90 to 95. Fibers from the unilateral retina were observed to terminate more in the contralateral nucleus. With regard to the suprachiasmatic nucleus, however, the terminations were observed to be distributed evenly and bilaterally.