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Title: Lysophosphatidic acid synthesis and phospholipid metabolism in rat mast cells

Abstract

The role of lysophosphatidic acid in mast cell response to antigen was investigated using an isolated rat serosal mast cell model. The cells were incubated with monoclonal murine immunoglobulin E to the dinitrophenyl hapten and prelabeled with /sup 32/P-orthophosphate or /sup 3/H-fatty acids. Lysophosphatidic acid was isolated form cell extracts by 2-dimensional thin-layer chromatography, and the incorporated radioactivity was assessed by liquid scintillation counting. Lysophosphatidic acid labeling with /sup 32/P was increased 2-4 fold within 5 minutes after the addition of antigen or three other mast cell agonists. Functional group analyses unequivocally showed that the labeled compound was lysophosphatidic acid. Lysophosphatidic acid synthesis was dependent on the activity of diacylglycerol lipase, suggesting formation from monoacylglycerol. In addition, the studies of lysophosphatidic acid synthesis suggest that the addition of antigen to mast cells may initiate more than one route of phospholipid degradation and resynthesis. Whatever the origin of lysophosphatidic acid, the results of this study demonstrated that lysophosphatidic acid synthesis is stimulated by a variety of mast cell agonists. Dose-response, kinetic, and pharmacologic studies showed close concordance between histamine release and lysophosphatidic acid labeling responses. These observations provide strong evidence that lysophosphatidic acid plays an important role in mast cell activation.

Authors:
Publication Date:
Research Org.:
Texas Univ., Houston (USA). Health Science Center
OSTI Identifier:
6703340
Resource Type:
Book
Resource Relation:
Other Information: Thesis
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; CARBOXYLIC ACIDS; BIOSYNTHESIS; MAST CELLS; CHEMICAL ACTIVATION; PHOSPHOLIPIDS; METABOLISM; ANTIGENS; BIOLOGICAL MODELS; DOSE-RESPONSE RELATIONSHIPS; IMMUNOGLOBULINS; PHOSPHATES; PHOSPHORUS 32; RATS; SCINTILLATION COUNTING; THIN-LAYER CHROMATOGRAPHY; TRITIUM COMPOUNDS; ANIMAL CELLS; ANIMALS; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; CHROMATOGRAPHY; CONNECTIVE TISSUE CELLS; COUNTING TECHNIQUES; DAYS LIVING RADIOISOTOPES; ESTERS; GLOBULINS; ISOTOPES; LABELLED COMPOUNDS; LIGHT NUCLEI; LIPIDS; MAMMALS; NUCLEI; ODD-ODD NUCLEI; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC PHOSPHORUS COMPOUNDS; OXYGEN COMPOUNDS; PHOSPHORUS COMPOUNDS; PHOSPHORUS ISOTOPES; PROTEINS; RADIOISOTOPES; RODENTS; SEPARATION PROCESSES; SOMATIC CELLS; SYNTHESIS; VERTEBRATES 550201* -- Biochemistry-- Tracer Techniques

Citation Formats

Fagan, D.L.. Lysophosphatidic acid synthesis and phospholipid metabolism in rat mast cells. United States: N. p., 1986. Web.
Fagan, D.L.. Lysophosphatidic acid synthesis and phospholipid metabolism in rat mast cells. United States.
Fagan, D.L.. 1986. "Lysophosphatidic acid synthesis and phospholipid metabolism in rat mast cells". United States. doi:.
@article{osti_6703340,
title = {Lysophosphatidic acid synthesis and phospholipid metabolism in rat mast cells},
author = {Fagan, D.L.},
abstractNote = {The role of lysophosphatidic acid in mast cell response to antigen was investigated using an isolated rat serosal mast cell model. The cells were incubated with monoclonal murine immunoglobulin E to the dinitrophenyl hapten and prelabeled with /sup 32/P-orthophosphate or /sup 3/H-fatty acids. Lysophosphatidic acid was isolated form cell extracts by 2-dimensional thin-layer chromatography, and the incorporated radioactivity was assessed by liquid scintillation counting. Lysophosphatidic acid labeling with /sup 32/P was increased 2-4 fold within 5 minutes after the addition of antigen or three other mast cell agonists. Functional group analyses unequivocally showed that the labeled compound was lysophosphatidic acid. Lysophosphatidic acid synthesis was dependent on the activity of diacylglycerol lipase, suggesting formation from monoacylglycerol. In addition, the studies of lysophosphatidic acid synthesis suggest that the addition of antigen to mast cells may initiate more than one route of phospholipid degradation and resynthesis. Whatever the origin of lysophosphatidic acid, the results of this study demonstrated that lysophosphatidic acid synthesis is stimulated by a variety of mast cell agonists. Dose-response, kinetic, and pharmacologic studies showed close concordance between histamine release and lysophosphatidic acid labeling responses. These observations provide strong evidence that lysophosphatidic acid plays an important role in mast cell activation.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1986,
month = 1
}

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  • The synthesis of pulmonary phospholipids by offspring of diabetic female rats was assessed by means of high performance liquid chromatography combined with automated phosphate analysis. No changes in the pool sizes of the major phospholipids or their precursors were observed. However, offspring of both insulin-treated and untreated diabetic mothers displayed increased pulmonary lyso-phosphatidylcholine. The concentration of glycerylphosphorylcholine, the metabolic product of lyso-phosphatidylcholine, was also increased in these offspring, providing further evidence of a reduced reacylation pathway in the offspring of diabetic mothers. The concentration of phosphatidylglycerol was reduced in the lungs from offspring of diabetic mothers. Preliminary investigation suggested thatmore » the mechanism of insulin action on lungs from offspring of diabetic rats may be the diversion of substrate from lipid synthetic pathways into protein synthesis. The utilization of (14C)-labeled amino acids and carbohydrates by normal fetal rat lung, however, revealed no direct insulin effect on protein synthesis. The ability of the fetal lung to convert amino acids into Krebs Cycle intermediates was demonstrated.« less
  • This is a review on the role of lysophosphatidic acid in the regulation of bone function and bone cancer.
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