Purchase this article with an account.
D.A. van der List, J.L. Coombs, L.M. Chalupa; Normal Development of Retinal Ganglion Cell Morphological Properties in Mice Lacking the Beta2 Subunit of the Nicotinic Acetylcholine Receptor . Invest. Ophthalmol. Vis. Sci. 2006;47(13):3113.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
We assessed the role of cholinergic retinal activity in the normal development and refinement of retinal ganglion cells by comparing the morphological properties of these neurons in wild–type mice and beta2 knockouts (b2–/–) at two different ages, P8 and P20. In the younger group, spontaneous retinal waves of activity are known to reflect cholinergic synaptic inputs, while at P20 such waves are glutamate–mediated.
Retinal ganglion cells were labeled with Diolistics using DiI or by the expression of YFP. Labeled neurons were scanned by a confocal microscope and from the resulting images we reconstructed and quantified the salient morphological features that have been found useful for distinguishing among different ganglion cell classes. These measures included: extent of dendrites within the inner plexiform layer, size of the dendritic fields, dendritic branch length, number of branches, mean branch length, dendritic density, tortuosity, symmetry of dendritic fields, spine density and soma size.
All of these parameters were found not to be significantly different between wild–type and beta2 animals and this was the case at P8 as well as P20.
These results indicate that cholinergic–mediated activity in the developing retina is not required for the normal postnatal development of retinal ganglion cells. Our findings suggest that the initial stratification and structural development of ganglion cells is independent of regulation by transmitter release until the later onset of glutamate–mediated activity.
This PDF is available to Subscribers Only