Patterns of X and Y optic nerve fibre terminations in the dorsal lateral geniculate nucleus of the cat.
The distributions of X and Y optic nerve fibre terminals in the A and A1 laminae of the dorsal lateral geniculate nucleus (LGNd) of the cat have been determined by a method that eliminates the Y fibres. A pressure-blocking technique was used in a sterile operation to produce anterograde degeneration in the Y fibres with minimal effect on the X fibres. Subsequently the Fink/Heimer technique was used to stain for degenerating fibres. This showed a strong peak of degeneration in the ventral regions of the laminae. Tritiated leucine was injected into one eye either of a normal cat or of one in which the optic nerve had been pressure-blocked at least one week previously. Subsequent examination of the LGNd by autoradiography showed a more uniform distribution of label in the laminae deprived of Y input (i.e. the pattern of distribution of X fibres). Subtraction of this distribution from that produced in a normal cat (i.e. X + Y input) gave the Y distribution. As in the degeneration studies, this revealed a peak of label in the most ventral part of each lamina but also showed a smaller peak in the most dorsal regions.
Westland
K W
KW
Department of Physiology (F13), University of Sydney, NSW 2006, Australia.
Burke
W
W
D000818:Animals; D001345:Autoradiography; D002415:Cats / Q000033:anatomy & histology*; D005829:Geniculate Bodies / Q000648:ultrastructure*; D007930:Leucine / Q000493:pharmacokinetics; D009410:Nerve Degeneration / Q000209:etiology / Q000473:pathology; D009411:Nerve Endings / Q000648:ultrastructure*; D009412:Nerve Fibers / Q000648:ultrastructure*; D009900:Optic Nerve / Q000648:ultrastructure*; D011312:Pressure; D013194:Staining and Labeling; D014316:Tritium
D014316:Tritium; D007930:Leucine