Plasma membrane appearance of phosphatidylethanolamine in stimulated macrophages

Journal Article · Mon Jul 01 04:00:00 EDT 1991 · Journal of Leukocyte Biology; (United States)

OSTI ID:5317103

Sandra, A; Cai, J ^[1]

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1. Univ. of Iowa, Iowa City (USA)

Mouse peritoneal macrophages were labeled with (1-3H)ethanolamine, and the presence of radioactive (3H)phosphatidylethanolamine (PE) at the plasma membrane was monitored by reacting the cells with trinitrobenzene sulfonic acid (TNBS) under nonpenetrating conditions. Macrophages stimulated with either the calcium ionophore A23187 or zymosan demonstrated a larger proportion of radiolabeled PE in the plasma membrane than control, nonstimulated cells. In experiments in which macrophages were labeled with ethanolamine for increasing times, appearance of membrane 3(H)PE was stimulated as early as after 2 hr of labeling. Macrophages labeled for 24 hr, then stimulated and returned to fresh medium still reflected a higher amount of membrane 3(H)PE at 2 hr after the stimulation, suggesting stimulation results in long-term alterations in plasma membrane lipids. Protease-peptone-elicited macrophages, which are not stimulated by zymosan or ionophore, did not exhibit an increase in membrane 3(H)PE upon stimulation. The size of the TNBS-accessible radiolabeled PE pool increased proportionately with a second stimulation; however, a subsequent labeling of the cells with TNBS after brief warming increased the TNBS-accessible pool in control cells only. As shown in previous studies, macrophage stimulation resulted in an increased incorporation of lipid precursors into phospholipid. The mass of plasma membrane Tnp-PE relative to mass of PE was not increased in ionophore-treated macrophages in contrast to a small (approximately 22%) increase in zymosan-treated cells. These results are suggestive of alterations in lipid synthesis in stimulated macrophages and possible long-term changes in the structure and function of the plasma membrane of macrophages following stimulation.

• OSTI ID: 5317103
• Journal Information: Journal of Leukocyte Biology; (United States), Journal Name: Journal of Leukocyte Biology; (United States) Vol. 50:1; ISSN JLBIE; ISSN 0741-5400
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINES
ANIMAL CELLS
ANIMALS
BIOLOGICAL LOCALIZATION
BIOLOGICAL MATERIALS
BIOSYNTHESIS
BLOOD
BLOOD PLASMA
BODY FLUIDS
CELL CONSTITUENTS
CELL CULTURES
CELL MEMBRANES
CONNECTIVE TISSUE CELLS
ESTERS
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
LABELLING
LIPIDS
MACROPHAGES
MAMMALS
MATERIALS
MEMBRANES
MICE
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PERITONEUM
PHAGOCYTES
PHOSPHOLIPIDS
RODENTS
SEROUS MEMBRANES
SOMATIC CELLS
SYNTHESIS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES
ZYMOSAN