Summary
There is evidence, from a variety of species, that axons arising from the two eyes interact as they pass through the optic chiasma. In this paper we examine the effect of altering the composition of the normal chiasmatic environment on the course taken by regenerating axons in Xenopus. We show that the usual contralateral route of such axons in the optic chiasma is not affected by the absence of axons from the other eye. We have not observed any influence of embryonic enucleation, or eye removal before the onset of metamorphosis, on either the normal ipsilaterally projecting axons or the contralateral route taken by regenerating axons. Further, we have found no effect of the degeneration of the other projection, either for long or short periods of time, suggesting that axonal debris does not influence the course of regenerating axons. The simultaneous regeneration of the two projections also has no effect on the trajectory of regenerating axons. We conclude that in spite of the close association of axons from the two eyes in the chiasma, there is no interaction involved in Xenopus in the generation of the decussation pattern.
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References
Bohn RC, Stelzner DJ (1979) Aberrant retino-retinal pathway during early stages of regeneration in adult Rana pipiens. Brain Res 160:139–144
Bohn RC, Stelzner DJ (1981) The aberrant retino-retinal projection during optic nerve regeneration. III. Effects of crushing both nerves. J Comp Neurol 196:633–643
Fawcett JW (1985) Factors guiding regenerating retinotectal fibres in the frog Xenopus laevis. JEEM 90:233–250
Fraser SE, Hunt RK (1980) Retinotectal plasticity in Xenopus: anomalous ipsilateral projection following late larval eye removal. Dev Biol 79:444–452
Fritzsch B, Wilm C, Crapon de Caprona MD (1987) Ipsilateral retinofugal and retinopetal projections in normal and monocular cichlid fish. Neurosci Lett 78:259–264
Gaze RM, Fawcett JW (1983) Pathways of Xenopus optic fibres regenerating from normal and compound eyes under various conditions. JEEM 73:17–38
Gaze RM, Grant P (1978) The diencephalic course of regenerating retinotectal fibres in Xenopus tadpoles. JEEM 44:201–216
Godement P, Salaun J, Metin C (1987) Fate of uncrossed retinal projections following early or late prenatal monocular enucleation in the mouse. J Comp Neurol 255:97–109
Guillery RW (1988) Early monocular enucleation in foetal ferrets produce a decrease of uncrossed and an increase of crossed retinofugal components: a possible model for the albino abnormality. J Anat 164:73–84
Hoskins SG, Grobstein P (1985) Development of the ipsilateral retinothalamic projection in the frog Xenopus laevis. I. Retinal distribution of ipsilaterally projecting cells in normal and experimentally manipulated frogs. J Neurosci 5:911–919
Humphrey M (1984) The formation of nerve connections between the eye and visual centres during optic nerve regeneration in the frog Hyla moorei. Ph.D. Thesis, University of Western Australia, Department of Psychology
Kennard C (1981) Factors involved in the development of ipsilateral retinothalamic projections in Xenopus laevis. JEEM 65:199–217
Lazar G (1980) Long-term persistence, after eye removal, of unmyelinated fibres in the frog visual pathways. Brain Res 199:219–224
Matsumoto DE, Scalia F (1981) Long-term survival of centrally projecting axons in the optic nerve of the frog following destruction of the retina. J Comp Neurol 202:135–155
Sretavan DW, Shatz CJ (1986) Prenatal development of cat retinogeniculate axon arbors in the absence of binocular interactions. J Neurosci 6:990–1003
Straznicky C, Gaze RM (1982) The innervation of a virgin tectum by a double-temporal or double-nasal eye in Xenopus. JEEM 68:9–21
Straznicky C, Hiscock J (1983) Aberrant retinotectal projection induced by larval enucleation in Xenopus. Neurosci Lett 39:5–10
Taylor JSH, Gaze RM (1985) The effects of the fibre environment on the paths taken by regenerating optic nerve fibres in Xenopus. JEEM 89:383–401
Taylor JSH, Gaze RM (1990) The induction of an anomalous ipsilateral retinotectal projection in Xenopus laevis. Anat Embryol 181:393–404
Thanos S, Fujisawa H, Bonhoeffer F (1984) Elimination of ipsilateral retinotectal projections in mono-ophthalmic chick embryos. Neurosci Lett 44:143–148
Wilson MA, Taylor JSH, Gaze RM (1988) A developmental and ultrastructural study of the optic chiasma in Xenopus. Development 102:537–553
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Taylor, J.S.H., Gaze, R.M. The course of regenerating retinal axons in the frog chiasma: the influence of axons from the other eye. Anat Embryol 181, 405–412 (1990). https://doi.org/10.1007/BF00186913
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DOI: https://doi.org/10.1007/BF00186913