Abstract— Triglyceride has been isolated from brain by thin‐layer chromatography and determined by absorption of the carbonyl group at 1740 cm−1. The means of yields from whole mouse brain, whole rat brain, rat brain grey matter, rat brain stem, and incubated slices of rat brain cortex were 0.15–0.17 μmole/g tissue. The distribution of fatty esters varied from preparation to preparation. Palmitate, stearate and oleate usually occurred in greatest amounts. Hydrolysis of a preparation of triglyceride from whole rat brain with pancreatic lipase indicated that palmitate was equally distributed between the α and β esters. [1‐14C]Acetate was rapidly incorporated into triglyceride of slices of incubated rat brain cortex. When the resulting triglyceride was hydrolysed with pancreatic lipase the distribution of radioactivity amongst the hydrolysis products was consistent with both the α and β esters of the triglyceride having been radioactively labelled.

Noradrenaline stimulated the incorporation of oleate into choline glycerophospholipids of guinea-pig brain synaptic membranes incubated in sodium phosphate buffer. In the presence of 1 mm-NaF, noradrenaline stimulated the incorporation of oleate into the choline glycerophospholipids, phosphatidylinositol, ethanolamine glycerophospholipids, phosphatidylserine and phosphatidic acid of synaptic membranes incubated in 10 mm-Tris-HCl buffer. In Tris-CHl containing 1 mm-NaF, stimulation of incorporation of oleate into choline glycerophospholipids by noradrenaline was enhanced by ATP, CaCl2, MgCl2 and CoA plus dithiothreitol. The optimum concentration of CaCl2 for stimulation by 10 mum-noradrenaline was 10 mum. In the presence of CaCl2, the optimum concentration of ATP-2MgCl2 was in the range 0.1-1 mm. Acetylcholine, carbamoylcholine, 5-hydroxytryptamine, dopamine, histamine and gamma-aminobutyric acid also stimulated the incorporation of oleate into choline glycerophospholipids of synaptic membranes. Sigmoidal dose-response curves were obtained, similar to those obtained previously for stimulation by the same agonists of the hydrolysis of phosphatidylcholine by phospholipase A2 (Gullis & Rowe, 1975a). The initial rate of transfer of oleate from oleoyl-CoA to choline glycerophospholipid was similar to the initial rate of transfer from oleate-albumin, stimulated by noradrenaline. Transfer of oleate from oleoyl-CoA was not appreciably stimulated by noradrenaline, but was stimulated by ATP and MgCl2.

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