Control of the spatial distribution of sodium channels in the squid giant axon and its cell bodies
This chapter summarizes the progress in developing a model system for studying the control of neuronal Na channel distribution based on the squid giant axon and its cell bodies located in the giant fibre lobe (GFL) of the stellate ganglion. Patch clamp methods have been employed to test the functional integrity of Na channels in GFL neurones maintained in primary culture, and to map the spatial distribution in cell bodies and axons. GFL neurones in vitro establish and maintain a strongly polarized Na channel distribution similar to that displayed by the system in vivo. Several manipulations that disrupt this cellular polarity, including a novel effect of the glycosylation inhibitor tunicamycin, have been identified. This drug appears to selectively inhibit high-level expression of Na channels in axonal membrane. Specificity of neuronal function at the cellular level is largely dictated by the precise spatial distribution of membrane receptors and channels. In general, the functional properties of many channels and receptors have been well studied, and in some cases their spatial distributions have been carefully mapped. Although this information is vital to understanding nerve cell function, there is still a need to learn much more about the cell biological dynamics that control both the properties and the spatial distributions of these important membrane proteins. All neurones are functionally and morphologically polarized, and the number of cellular control elements is large.
Oxford Scholarship Online requires a subscription or purchase to access the full text of books within the service. Public users can however freely search the site and view the abstracts and keywords for each book and chapter.
If you think you should have access to this title, please contact your librarian.