In-Vitro and In-Vivo Studies on Gangliosides in the Developing and Regenerating Hippocampus of the Rat

Abstract

Gangliosides may have important biological functions in cell-cell recognition during development, for regenerative processes in the nervous system, as receptors or receptor modulators, and possibly in the process of synaptic transmission. In order to investigate some of these aspects we have used in our laboratory nerve cell cultures as model systems for studies on ganglioside functions.^1,2 In spite of their obvious advantages, neuroblastoma cell lines are inadequate models for such studies due to their lack of the higher polysialo-gangliosides² and due to their transformed properties as tumor derivatives. We have therefore developed in recent years a primary culture system of the developing rat hippocampus which allows in-vitro studies on development and synapse formation of pyramidal neurons.³ We report here some results on the ganglioside pattern of these hippocampal neurons. The hippocampus is known for its functional and morphological plasticity. Following entorhinal lesions and resulting degeneration in the area dentata, a regenerative process of axonal sprouting and renewed synapse formation is induced. In a parallel in-vitro study we have investigated changes in ganglioside biosynthesis during this process of regenerative synaptogenesis in the hippocampus of the adult rat.