Techniques for Examining the Effect of Substratum-Bound Proteoglycans on Neurite Outgrowth In Vitro

Techniques to investigate mechanisms affecting neurite outgrowth, in vitro, are invaluable to the neuroscience community. In particular, these techniques have enhanced our understanding of the role of the extracellular matrix (ECM) in neuronal regeneration following spinal cord injury (SCI). In this chapter, we explain two useful techniques that have been used in our laboratory to investigate the role of chondroitin sulfate proteoglycans (CSPGs) in the inhibition of neurite outgrowth: (1) the Stripe Assay (Snow et al., Exp Neurol 109(1):111–130, 1990), which is a widespread model used to determine the effect of a patterned substrata with a sharp gradient of bound CSPG on neurite outgrowth, and (2) the Step Gradient Assay (Snow and Letourneau, J Neurobiol 23(3):322–336, 1992), used to measure the response of neurites to a stepwise (less steep) increase in CSPGs. The Stripe Assay and Step Gradient Assay are considered to be “choice” assays, in which the sensorimotor, substratum-detecting portion of an elongating neurite, the growth cone, responds to changes in the ratio of growth-promoting to growth-inhibiting substratum-bound molecules. In addition to CSPGs, these methods can be used to test the responses of elongating neurites to a wide variety of extracellular matrix molecules or other proteins. Further, these assays can be used to study the ability of agents to overcome outgrowth inhibition. The results obtained from these methods can reveal mechanis...
Source: Springer protocols feed by Neuroscience - Category: Neuroscience Source Type: news