Thin-layer chromatographic analysis of myelin lipids, their differential O-deacylation by primary alkylamines and their selective staining by thionine. A limited phylogenetic study.

A silica gel thin-layer chromatographic procedure is described for the study of the myelin lipid patterns in a small phylogenetic series of nerve tissue specimens. It involves the selective staining by the thiazine dye thionine and the interpretations were facilitated by a preceding primary alkylamine O-deacylation step. Glycolipids, including sulfatides, and ethanolamine plasmalogens were the principal characterizing lipids.

On the plasmalogenation of myocardial choline glycerophospholipid during maturation of various vertebrates.

1. The plasmalogen profiles of a series of hearts from fish to mammals were obtained by various TLC analyses. 2. All specimens (ventricular) contained ethanolamine plasmalogen and some choline plasmalogen, as well. 3. The distribution of these two plasmalogen species was relatable, in part, to (a) phylogeny and (b) ontogeny. 4. There were exceptions. 5. The appearance of choline plasmalogen was preceded by its alkylacyl precursor, suggesting plasmalogenation by a base-specific delta 1-alkyl desaturase. 6. From the data, we have raised some questions as to the metabolic role played by the plasmalogens and precursors as occupants of myocardial mitchondrial membranes.

A correlative lipid and lipolytic study of the pancreas and small intestine of the guinea-pig.

With the aid of a variety of TLC preparations the phospholipid and neutral lipid profiles of guinea-pig pancreas and small intestine has been established. Changes in these profiles, subsequent to incubation of these tissues and prior to lipid extraction, has provided evidence relating to their respective lipolytic enzyme capabilities, mainly in the phospholipase group.

Some contributions to the thin-layer chromatographic analysis of complex natural phospholipid and neutral lipid mixtures.

We have isolated a minor phosphatidyl ethanolamine component from pancreas and a minor phosphatidyl choline component from retina, which were revealed by their separate thin-layer chromatographic properties on silica gel and aluminum oxide sheets, respectively. We have described in some detail a number of modifications in thin-layer chromatography methodology which enhances the opportunity for assessing the glycerophospholipid and neutral lipid composition of tissues, as attested by a diverse set of examples, and have pointed out some of the associated technical problems.

The melanins and lipofuscin.

An overview of the melanins and lipofuscin is presented, taking an integrating account of their morphological relationships and chemical characteristics wherever possible. This has required inclusion of the ommochromes, the schlerotizing process, and consideration of related neurotransmitters. A number of questions are raised and commented upon.

A reappraisal of the dog-heart infarct plasmalogen, its conception as a bis-phosphatidic acid and current recognition as an N-acyl phosphatidyl ethanolamine.

1. We have re-examined the lipids from myocardial infarcts of cat, dog, rabbit and man, mainly through TLC methods, and confirm the identity of cat and dog "infarct plasmalogen" as an N-acyl phosphatidyl ethanolamine (NAPE). This substance was not detected in infarcts of rabbit and man. 2. We have extended our observations on a similar phosphatide, as the plasmalogen form, naturally occurring in the brain and optic nerve of fish. 3. Supporting evidence for the NAPE identity was provided from non-plasmalogen forms isolated from peas and lentils. 4. NAPE in all of its forms was shown to be a reluctant substrate for the phospholipase A2 of snake venoms. 5. Co-chromatography problems involving NAPE, semi-lyso cardiolipin and bis-phosphatidic acid are documented and their relationship to the infarct phenomenon discussed.

Studies on the endogenous phosphatides of mammalian pancreas and their hydrolysis by endogenous phospholipases - I. The lipids of dog pancreas and their in vitro hydrolysis, primed by trypsin, by phospholipase A2.

1. The phosphoglyceride and sphingolipid content of dog pancreas has been determined and their in vitro response to the endogenous lipolytic enzymes, initiated by trypsin, at pH 7.4 was examined by TLC technology. 2. The glyceryl ether phosphatides were found to consist primarily of PE and PC, each with alkyl and alk-1-enyl components both of which were hydrolyzed to their respective 1-radyl lyso derivatives under the described incubation conditions. 3. A new TLC visualizing reaction for lipids, OSPAS, is described.

Chromatographic analysis of the neutral and phosphatide glyceryl ethers from various biological sources.

A method of analysis is described which permits the facile evaluation of the neutral glyceryl ether lipids (mild alkaline hydrolysis) and total glyceryl ether lipid (Vitride reduction) thereby allowing an assessment of the phosphatide contribution. The alkyl and alk-enyl glyceryl ethers are chromatographically resolvable on Gelman glass-fiber type SG and Whatman SG-81 and detected by the periodic acid-Schiff and plasmal reaction, respectively. The attending problems and interpretation are discussed with examples from a number of unicellular organisms and animal tissues.