Mechanisms of glucocorticoid induced suppression of phagocytosis in murine peritoneal macrophage cultures

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:5347260

Becker, J L

Glucocorticoids suppress phagocytosis of heat killed Saccharomyces cerevisiae in macrophage cultures. In order to determine the mechanisms by which this response occurs, this investigation was initiated to examine whether the suppression of phagocytosis is mediated by a steroid induced phagocytosis inhibitory protein (PIP). Furthermore, it is postulated that these suppressive effects may be associated with alterations in macrophage phospholipid metabolism. To assess the association between phospholipid metabolism and phagocytosis, control and 1 ..mu..M dexamethasone treated macrophages were exposed to the phospholipase inhibitor bromophenacylbromide. The enzyme inhibitor suppressed phagocytosis in a time and dose dependent manner. However, supplying dexamethasone treated cultures with arachidonate did not reverse the steroid induced suppression of phagocytosis, whether the arachidonate was supplied alone or together with indomethacin and nordihydroguaiaretic acid. Control cells, prelabeled with /sup 3/H-arachidonate, exhibited an increased percentage of the radiolabeled fatty acid in neutral lipids following phagocytosis, with a corresponding decrease in the percentage associated with phosphatidylcholine.

• Research Organization: University of South Florida, Tampa (USA)
• OSTI ID: 5347260
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ADRENAL HORMONES
ANIMAL CELLS
ANIMALS
ARACHIDONIC ACID
BIOLOGICAL EFFECTS
CARBOXYLIC ACIDS
CELL CULTURES
CONNECTIVE TISSUE CELLS
CORTICOSTEROIDS
DOSE-RESPONSE RELATIONSHIPS
ENZYME INHIBITORS
ESTERS
FUNGI
GLUCOCORTICOIDS
HORMONES
HYDROXY COMPOUNDS
INHIBITION
ISOTOPE APPLICATIONS
KETONES
LABELLED COMPOUNDS
LIPIDS
MACROPHAGES
MAMMALS
METABOLISM
MICE
MICROORGANISMS
MONOCARBOXYLIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHAGOCYTES
PHAGOCYTOSIS
PHOSPHOLIPIDS
PLANTS
PREGNANES
RODENTS
SACCHAROMYCES
SACCHAROMYCES CEREVISIAE
SOMATIC CELLS
STEROID HORMONES
STEROIDS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES
YEASTS