Lipid metabolism of developing central nervous tissues in organotypic cultures. III. Ganglionic control of glycerolipids and fatty acids in cortex grey matter.

Lipid changes in rat brain grey matter were observed in a coculture system of innervating and target explants. The de novo biosynthesis of individual glycerolipids and the metabolism of fatty acids were investigated. Innervating grey matter cultures exhibited a substantial increase in neutral glycerolipid formation. Only slight modifications were observed in the fatty acid fraction. Target cells responded to innervation by a marked increase in phosphatidylcholine, phosphatidylinositol, and phosphatidylethanolamine formation. In addition, the biosynthesis of arachidonate and docosahexaenoate was drastically enhanced. It is shown that neuritic bridges connecting the explants, rather than soluble factors, account for the effects observed. Putative mechanisms involved in changes of lipid metabolism are discussed.