Biochemical evidence on the role of gangliosides in nerve-endings.

From the biochemical and developmental data in the literature, there appears to be some specific relationship of gangliosides to synapses. Whether the concentration of polysialo-gangliosides is located in the immediately pre-synaptic part of the neuronal plasma membrane is not known. There are many unanswered questions about the gangliosides, which we have attempted to pose in this article. There are as many hypotheses about roles for gangliosides, and virtually no data to back them up. In fact there are not even real indications of possible functions. We believe that it will be very difficult to define the functions of gangliosides until more of the basic questions are answered-even if their synaptic localization is a constant temptation to speculate.