Retinogeniculate Axons Undergo Eye-Specific Segregation in the Absence of Eye-Specific Layers

• Published in: The Journal of neuroscience Vol. 22; no. 13; pp. 5259 - 5264
• Main Authors: Muir-Robinson, Gianna, Hwang, Bryan J, Feller, Marla B
• Format: Journal Article
• Language: English
• Published: United States Soc Neuroscience 01.07.2002; Society for Neuroscience
• Subjects: Animals; Axons - ultrastructure; Brief Communication; Geniculate Bodies - cytology; Geniculate Bodies - growth & development; Kinetics; Mice; Mice, Knockout; Receptors, Glutamate - metabolism; Receptors, Nicotinic - genetics; Retina - cytology; Retina - growth & development; Retinal Ganglion Cells - cytology; Visual Pathways
• ISSN: 0270-6474; 1529-2401
• DOI: 10.1523/jneurosci.22-13-05259.2002

Spontaneous retinal activity mediated by cholinergic transmission regulates the segregation of retinal ganglion cell axons in the lateral geniculate nucleus of the thalamus into eye-specific layers. The details of how the layers form are unknown. Mice lacking the beta2 subunit of the neuronal nicotinic acetylcholine receptor lack ACh-mediated waves and as a result, do not form eye-specific layers at any stage of development. However, during the second postnatal week, beta2-/- mice have glutamate-mediated waves. Here we show that after the first postnatal week, even in the absence of layers, retinothalamic axons segregate into an unlayered, patchy distribution of eye-specific regions. These results indicate that spontaneous neural activity may independently regulate eye-specific segregation and the formation of layers at the developing retinothalamic projection.