Characterization and comparison of lipids in different squid nervous tissues

Abstract

We have studied the lipid composition of brain (optic and cerebral lobes), stellate ganglia and fin nerves of the squid. Cholesterol, phosphatidylethanolamine and phosphatidylcholine were the major in nervous tissues. Phosphatidylethanolamine contained about 3% of its amount of plasmalogen forin. Phosphatidylserine and -inositol, sphingomyelin and eeramide 2-aminoethylphosphonate were also present in significant amounts. In addition, cardiolipin and free fatty acids were detected in brain (each 2–3% of totle lipids) and steliate ganglia (about 1% each), but not in fin nerves. Phosphatidylethanolamaine, dylserine and phosphatidylinositol from brain contained large amounts of polyunsaturated fatty acid, namely 20:4, 20:5 and 22:6 in the n−3 family. On the other hand, phosphatidylcholine, eardiolipin, and sphingomyelin, and ceramide 2-aminoethylphosphonate contained only saturated or monounsaturated C 16-C 18 fatty acids. The aldehyde moieties of cthanolamine plasmalogen were also C 16-C 18 saturated or monounsaturated. These lipid compositions are compared with those in other invertebrate nervous systems.