NBD-cholesterol incorporation by rat macrophages and lymphocytes: a process dependent on the activation state of the cells.
The time-course of incorporation of NBD-cholesterol by macrophages (Ma) and lymphocytes (LY) obtained from untreated and thioglycollate-injected (thio) rats was investigated. NBD-cholesterol incorporation was also examined in Ma obtained from untreated rats and stimulated in vitro by lipopolysaccharide (LPS) and phorbol-myristate acetate (PMA). The same measurement was performed in LY from untreated rats stimulated by addition of LPS and concanavalin A (Con A) into the culture medium. Thio-treated Ma showed high fluorescence intensity after 1 h of incubation with NBD-cholesterol. Ma submitted concomitant to LPS and NBD-cholesterol showed low fluorescence intensity, as well as Ma stimulated with PMA. Ma from untreated and LPS pre-treated rats showed a similar time-course of incorporation. LY from thio-treated rats showed lower incorporation of NBD-cholesterol in comparison to LY from untreated rats. Incorporation was reduced when LPS was added concomitantly with NBD-cholesterol. On the other hand, LY pre-treated with LPS for 48 h showed a very high incorporation of NBD-cholesterol. Con A treatment did not cause a significant effect on NBD-cholesterol incorporation. The findings presented herein led us to conclude that the uptake of NBD-cholesterol by Ma and LY is markedly affected by the activation state of the cells.
Portioli Silva
Erica P
EP
Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, SP, Brazil. ericaportisan@uol.com.br
Peres
Carmem M
CM
Roberto Mendonça
José
J
Curi
Rui
R
D009327:4-Chloro-7-nitrobenzofurazan / Q000031:analogs & derivatives* / Q000378:metabolism*; D000818:Animals; D002784:Cholesterol / Q000031:analogs & derivatives* / Q000378:metabolism*; D003208:Concanavalin A / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D008262:Macrophage Activation / Q000187:drug effects; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
C077527:7-nitrobenz-2-oxa-1,3-diazol-4-ylcholesterol; D008070:Lipopolysaccharides; D003208:Concanavalin A; D002784:Cholesterol; D009327:4-Chloro-7-nitrobenzofurazan; D013755:Tetradecanoylphorbol Acetate