ALKALINIZING THE INTRALYSOSOMAL PH INHIBITS DE-GRANULATION OF HUMAN-NEUTROPHILS
ALKALINIZING THE INTRALYSOSOMAL PH INHIBITS DE-GRANULATION OF HUMAN-NEUTROPHILS
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DOI：
10.1172/jci111139
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发表时间：
1983-01-01
影响因子：
15.9
通讯作者：
STYRT, B
中科院分区：
文献类型：
--
作者：
KLEMPNER, MS;STYRT, B
Degranulation of lysosomes is 1 of the consequences of neutrophil activation. Regulatory mechanisms of lysosomal secretion are thought to be localized largely in the plasma membrane and cytosol, with the lysosome playing a passive role in secretion. Recent evidence indicates that the intralysosomal pH is highly acidic (pH .simeq. 5.5) and is maintained by active transport of H+. Whether changes in the intralysosomal pH altered the availability of lysosomes for exocytosis were investigated. Intralysosomal pH in intact neutrophils was monitored with the weakly basic fluorescent probe, 9-aminoacridine (9AA). The weak bases, methylamine, chloroquine, clindamycin, propanolol and ammonium chloride (0.1-50 mM), caused an alkalinization of the intralysosomal pH as determined by reversal of quenching of 9AA fluorescence. Similarly, each of the weak bases, including ammonium chloride, methylamine, chloroquine, ethylamine, propylamine, propanolol, clindamycin and dansylcadaverine, inhibited neutrophil degranulation in response to the Ca ionophore A23187, phorbol myristate acetate, or the chemotactic peptide, f-met-leu-phenylalanine plus cytochalasin B. Evidently, an acid intralysosomal pH is important to the neutrophil secretory response and suggest that the lysosome may play an active part in control of degranulation.
