Opsonized zymosan decreases cytoplasmic motility of alveolar macrophages in dogs.
To examine the mechanisms of changes in alveolar macrophage (AM) activities caused by phagocytic stimulus, we studied the effect of opsonized zymosan (OZ) on cytoplasmic motility (CM) of AM from dog lungs in vitro. Four days after the instillation of ferrimagnetic particles (Fe3O4, 3 mg/kg) into the lower lobe bronchus, AM were harvested by broncho-alveolar lavage. AM were adhered to the bottom of plastic vials (10(6) cells of AM per each vial). Remanent field strength (RFS) from the AM containing Fe3O4 particles was measured immediately after magnetization. RFS decreased with time due to particle rotation (relaxation), which is related to cytoplasmic motility of AM. OZ (1-500 micrograms) decreased lambda 0 (the relaxation rate for the first min) in a concentration-dependent fashion. Neither BW755C (10(-5) M), indomethacin (10(-6) M), leupeptin (10(-5) M), bestatin (10(-5) M), nor superoxide dismutase (1000 U/ml) inhibited OZ (500 micrograms)-induced inhibitory effects on lambda 0, suggesting that cyclooxygenase and lipoxygenase products, serine, thiol enzymes, aminopeptidase and superoxide anion wer not responsible for OZ-induced effects. OZ (500 micrograms) significantly increased the intracellular concentration of Ca2+ (P less than 0.01). Likewise, OZ (500 micrograms)-induced effects on lambda 0 of AM were significantly inhibited by replacement of the medium with a Ca2+ free solution (P less than 0.01). These results imply that opsonized zymosan inhibits cytoplasmic motility of AM via external calcium influx.
Zayasu
K
K
First Department of Internal Medicine, Tohoku University School of Medicine, Sendai, Japan.
Fukushima
T
T
Yamaya
M
M
Sekizawa
K
K
Yamauchi
K
K
Sasaki
H
H
Takishima
T
T
D015772:4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amine / Q000494:pharmacology; D000626:Aminopeptidases / Q000037:antagonists & inhibitors; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002216:Captopril / Q000494:pharmacology; D002478:Cells, Cultured; D003593:Cytoplasm / Q000378:metabolism / Q000502:physiology*; D004285:Dogs; D007213:Indomethacin / Q000494:pharmacology; D007930:Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D007976:Leupeptins / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000502:physiology*; D010587:Phagocytosis / Q000502:physiology; D011650:Pulmonary Alveoli / Q000166:cytology; D013482:Superoxide Dismutase / Q000378:metabolism; D015054:Zymosan
D007976:Leupeptins; D015772:4,5-Dihydro-1-(3-(trifluoromethyl)phenyl)-1H-pyrazol-3-amine; D015054:Zymosan; D002216:Captopril; D013482:Superoxide Dismutase; D000626:Aminopeptidases; D007930:Leucine; C012211:ubenimex; C032854:leupeptin; D002118:Calcium; D007213:Indomethacin