The effect of lysolecithin (lysophosphatidylcholine) on the relaxation of rabbit aortic strip closely resembled that produced by acetylcholine (ACh) which releases the endothelium-derived relaxing factor (EDRF). Relaxation induced by lysolecithin depended on the presence of endothelium and was inhibited by hemoglobin and methylene blue. It appeared to be mediated by the second messenger, c-GMP....

AIMS To examine the potential role of the lipolytic enzyme phospholipase A2, produced by Helicobacter pylori in ulcer formation. METHODS Phospholipase A2 activity in H pylori was compared with that in 10 commonly occurring pathogenic bacteria. Phospholipase A2 activity and its cytotoxic metabolite, lysolecithin, in the basal gastric aspirates of 12 patients infected with H pylori were compare...

The effect of lysolecithin (100 mg%) on the guinea-pig gastric mucosa was studied by instilling a solution for 30 minutes, preceded and followed by 100 MN HCl into 10 total gastric pouches. Ten control animals had HCl throughout. Lysolecithin produced a significant change in transmucosal potential difference, macroscopic erosions, and mucosal damage on histology and electron scanning microscopy...

Washed rabbit platelets were resuspended in plasma in which all of the major phospholipids had been isotopically labeled by injection of 32PO4 into rabbits. At certain time intervals during a 6-hr incubation at 37 degrees C, aliquots were removed from the incubation mixture and the platelets were isolated and subjected to lipid extraction and phospholipid analysis. A continuous rise in platelet...

The metabolic fate of (14)C-labeled fatty acids which have been incubated with human platelets, has been traced. The following has been shown. (a) Intact platelets have a considerable capacity to oxidize fatty acids. (b) When tracer amounts of four of the most common fatty acids in normal plasma were incubated with platelets, each showed a distinctive pattern of uptake among neutral lipids and ...

The effect of lysolecithin on the shape of human erythrocytes of varied cholesterol content was examined by scanning electron microscopy. Under the conditions of these experiments, all of the [14C]lysolecithin incubated with cells was shown to be located in the external membrane leaflet. The membrane lysolecithin required to induce echinocytosis (spiculation) in normal cells (0.8 mol cholestero...

The effects of lysolecithin and of 2 synthetic ether-desoxy lysolecithin analogs, containing alkyl residues of 16 or 12 carbon atoms, on the agglutination kinetics of calf and rabbit thymocytes by concanavalin A (Con A) were investigated. Unlike the natural lysolecithin, these synthetic analogs are resistant to metabolism by membrane associated enzymes. It was found that pretreatment of thymocy...

There is in normal plasma an enzyme activity which converts labeled lysolecithin to lecithin by an energy-independent low density lipoprotein-activated pathway. Studies were undertaken to compare the identity of this enzyme with lecithin-cholesterol acyltransferase. During purification of the enzyme by ultracentrifugation and by chromatography on high density lipoprotein affinity column, DEAE-S...

OELLERMANN, R. A., HOOGENHOUT, JOAN and CARTER, P. Phagocytic activity of peritoneal exudate cells from mice. Onderstepoort]. vet. Res. 39(4), 197-204 (1972). . Phago~ytic activity of peritoneal exudate cells in mice was stimulated by injection of 0,1 ml mineral 01l or varymg concentrations of lysolecithin. Optimal lysolecithin concentration was found to be 2 to 5 11-g pe~ mous~. The phagocytic...