Lipids and Related Compounds

Lipids m the nervous system are major components of the m- branes. The presence of glycolipids in high concentrations is unique for the nervous system. Recent discoverres of the functronal and pathological importance of lipids such as diacylglycerols, polyphosphoinositides, prostaglandins, leukotrienes, docosahexaenoic acid, platelet activating factor, and gangliosides have markedly increased the number of publications on nervous system lipids. Many new methods have been developed. Thus, there IS a need for this volume that is dedicated to that methodo- gy. This volume places all of the methods for lipids into perspective with recommendations concerning the selection of a method for a specific purpose. Lloyd A. Horrocks vii Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Preface to the Series vi Preface.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. ............................... xix List of Contributors Lipid Extraction Norman S. Radin 1 1. Introduction ...................................................... ......................................... 5 2. Properties of Solvents 2.1. Ethers ........................................................ 6 8 2.2. Alcohols ..................................................... 9 2.3. Halocarbons ................................................ 9 2.4. Hydrocarbons ............................................. 2.5. Miscellaneous Solvents ................................ 10 .................................... 10 3. Storage of Lipid Extracts 14 4. Homogenizers .................................................. ..... 15 5. Separating the Extract from the Tissue Residue 15 5.1. Use of Filtration .......................................... 16 5.2. Centrifugation ............................................ .............. 17 6. Removing Nonlipids from Lipid Extracts 6.1. Removal of Nonlipids by Evaporation and Reextraction ............................................... 17 .................... 17 6.2. Prewashing the Tissue Sample.. 6.3. Removal of Nonlipids by Precipitating the Lipids with the Proteins ............................... 18 ............................ 19 6.4. Liquid/Liquid Partitioning .................. 19 6.5. Removal of Nonlipids by Dialysis 6.6. Separation from Nonlipids by Changing a 21 Partition Constant .......................................