title: The pinocytic rate of activated macrophages.
abstract: Peritoneal macrophages from mice injected 4 days previously with Brewer's thioglycollate medium have a pinocytic rate, in culture, of 190 ng horseradish peroxidase (HRP)/100 mug cell protein/h, compared to the rate of resident peritoneal cells of 53 ng HRP/100 mug cell protein/h. Mice injected with endotoxin or with only certain of the components of the Brewer's medium show an intermediate level of stimulation. The rate of unstimulated, endotoxin-stimulated, or thioglycollate-stimulated cells shows little change over several days in culture. The pinocytic rate of thioglycollate-stimulated cells can, however, be further increased by exposure of concanavalin A. Although cells may show transient increases in their pinocytic rate in many situations, a sustained increase in pinocytic rate is a sign of the "activated" state of macrophages.
mesh_terms: D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D002452:Cell Count; D002478:Cells, Cultured; D004731:Endotoxins / Q000276:immunology; D005260:Female; D006735:Horseradish Peroxidase; D008264:Macrophages / Q000276:immunology* / Q000648:ultrastructure; D008297:Male; D051379:Mice; D010873:Pinocytosis; D013194:Staining and Labeling; D013864:Thioglycolates / Q000276:immunology
chemical_list: D004731:Endotoxins; D013864:Thioglycolates; D006735:Horseradish Peroxidase