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Distribution of uncrossed and crossed retinofugal axons in the cat optic nerve and their relationship to patterns of fasciculation

Published online by Cambridge University Press:  02 June 2009

Glen Jeffery
Glen Jeffery
Affiliation:
Department of Human Anatomy, University of Oxford, OX1 3QX, United Kingdom
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Abstract

The course of optic axons that take different routes at the chiasm have been traced through horizontally sectioned optic nerves in the cat, after unilateral injections of horseradish peroxide into the optic tract. Behind the eye and for most of the course of the nerve, nearly all of the axons that remain uncrossed at the chiasm are located in a retinotopically appropriate position, in the lateral aspect of the nerve. However, in the most caudal segment of the nerve an increasing proportion of these axons are located in regions that are retinotopically inappropriate. Just before the nerve joins the chiasm, uncrossed axons can be found across the full medio-lateral extent of the nerve, although there is still a relative increase in their density laterally.

Labeled axons that cross at the chiasm course in a relatively parallel manner along the greater proportion of the nerve. However, in the caudal segment of the nerve their relative positions change and they appear to course in an irregular manner. This occurs where the uncrossed projection becomes increasingly more widespread.

Axons in the optic nerve are grouped into fascicules. This pattern of organization also changes in the caudal region of the nerve. Although clear fascicular patterns are present along the greater part of the nerve, they become progressively less distinct caudally. The change in the pattern of fasciculation occurs over the same region of the nerve as the relative changes in axon trajectory and distribution.

These results demonstrate that irrespective of chiasmatic route, optic axons in the cat are reorganized in the caudal segment of the nerve. This reorganization is not confined to changes in relative axon position, but is reflected in the structure of the nerve by the change of axon grouping from a fascicular to a non-fascicular arrangement.

Keywords

Optic nerveRetinotopic orderFasciculation
Type
Research Article
Information
Visual Neuroscience , Volume 5 , Issue 1 , July 1990 , pp. 99 - 104
Copyright
Copyright © Cambridge University Press 1990

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References

Baker, G.E. (1990). Prechiasmatic reordering of fiber diameter classes in the retinofugal pathway of ferrets. European Journal of Neuroscience 2, 24–33.Google Scholar
Baker, G.E. & Jeffery, G. (1989). Distribution of uncrossed axons along the course of the optic nerve and chiasm of rodents. Journal of Comparative Neurology 289, 455–461.Google Scholar
Bunt, A.H., Minckler, D.S. & Johanson, G.W. (1977). Demonstration of bilateral projection of the central retina of the monkey with horseradish peroxidase neuronography. Journal of Comparative Neurology 171, 619–630.Google Scholar
Cooper, M.L. & Pettigrew, J.D. (1979). The decussation of the retinothalamic pathway in the cat, with a note on the major meridians of the cats eye. Journal of Comparative Neurology 187, 285–312.CrossRefGoogle ScholarPubMed
Donovan, A. (1967). The nerve fiber composition of the cat optic nerve. Journal of Anatomy 101, 1–11.Google ScholarPubMed
Guillery, R.W., Polley, E.H. & Torrealba, F. (1982). The arrangement of axons according to fiber diameter in the optic tract of the cat. Journal of Neuroscience 2, 714–721.Google Scholar
Guillery, R.W. & Walsh, C. (1987). Changing glial organization relates to changing fiber order in the developing optic nerve of ferrets. Journal of Comparative Neurology 265, 203–217.Google Scholar
Hanker, J.S., Yates, P.E., Metz, C.B. & Rustioni, A. (1977). A new specific sensitive and non-carcinogenic reagent for the demonstration of horseradish peroxidase. Histochemical Journal 9, 789–792.Google Scholar
Horton, J.C., Greenwood, M.M. & Hubel, D. (1979). Nonretinotopic arrangement of fibers in the cat optic nerve. Nature 282, 720–722.Google Scholar
Hughes, A. & Wassle, H. (1976). The cat optic nerve: fiber total count and diameter spectrum. Journal of Comparative Neurology 169, 172–184.Google Scholar
Jeffery, G. (1989). Distribution and trajectory of uncrossed axons in the optic nerves of pigmented and albino rats. Journal of Comparative Neurology 289, 462–466.Google Scholar
Jeffery, G., Cowey, A. & Kuypers, H.G.J.M. (1981). Bifurcating retinal ganglion cell axons in the rat, demonstrated by retrograde double labeling. Experimental Brain Research 44, 34–40.CrossRefGoogle Scholar
Mesulam, M.M. (1978). Tetramethyl benzidine for horseradish peroxidase neurohistochemistry: a non-carcinogenic blue reaction product with superior sensitivity for visualizing neural afferents and efferents. Journal of Histochemistry and Cytochemistry 26, 106–117.CrossRefGoogle ScholarPubMed
Naito, J. (1986). Course of retinogeniculate projection fibers in the cat optic nerve. Journal of Comparative Neurology 251, 376–387.Google Scholar
Naito, J. (1989). Retinogeniculate projection fibers in the monkey optic nerve: a demonstration of fiber pathways by retrograde axonal transport of WGA-HRP. Journal of Comparative Neurology 284, 174–186.Google Scholar
Polyak, S. (1957). The Vertebrate Visual System. Illinois: The University of Chicago Press.Google Scholar
Stons, J. (1966). The naso-temporal division of the cat's retina. Journal of Comparative Neurology 126, 585–600.Google Scholar
Stone, J. (1981). The Wholemount Handbook. Sydney, Australia: Maitland Publications.Google Scholar
Walsh, C. (1986). Age-related fiber order in the ferret's optic nerve and optic chiasm. Journal of Neuroscience 6, 1635–1642.Google Scholar
Williams, R.W. & Chalupa, L.M. (1983). An analysis of axon caliber within the optic nerve of the cat: evidence of size groupings and regional organization. Journal of Neuroscience 3, 1554–1564.Google Scholar