Neuritic Responses to GM1 Ganglioside in Several in Vitro Systems

Abstract

In explant or monolayer neural cultures, a neuron is subject to various influences from the medium, the substratum, and the other cells present. Medium components also alter the substratum properties, and cultured cells modify both medium and substratum besides themselves via direct contacts. This multiplicity of influence sources applies in vivo, and in pathological as well as normal circumstances. If the balance of such extrinsic influences is already optimal for the neural performance to be investigated, then experimental interventions cannot reveal agents with a promoting effect but only agents with an inhibiting influence. To seek and investigate a beneficial (promoting) agent one must rely on restrictive circumstances, either imposed experimentally or occuring naturally as may be the case in developmental or pathological situations.