Calcium ionophore A23187 enhances human neutrophil superoxide release, stimulated by phorbol dibutyrate, by converting phorbol ester receptors from a low‐ to high‐affinity state

FEBS Letters

Valente, L.¹  Forbes, I.J.¹  French, J.K.¹  Zaiewski, P.D.¹  Hurst, N.P.¹ 

[1] The Queen Elizabeth-Royal Adelaide Hospital Rheumatology Unit and University of Adelaide Department of Medicine, Adelaide, South Australia, Australia

关键词: Ca2+;    Ionophore A23187;    Phorbol ester;    Protein kinase C;    Neutrophil;    PDBu;    phorbol dibutyrate;    PMN;    neutrophil polymorphonuclear leucocyte;    TMB-8;    3;    4;    5-trimethoxybenzoic acid 8-(diethylamino)octyl ester;   

DOI  :  10.1016/0014-5793(87)81353-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The calcium ionophore A23187 acted synergistically with phorbol dibutyrate (PDBu) to stimulate human neutrophil superoxide production. A23187 shortened the lag period and markedly increased the initial rate of neutrophil superoxide production induced by suboptimal concentrations of PDBu. l μM A23187 reduced the EC₅₀ value for superoxide release from 56 to 8 nM PDBu. This effect of A23187 was correlated with enhanced binding of [³H]PDBu to its receptor and a reduction in the dissociation constant (K _d) from 27 to 10 nM, without altering the apparent total number of phorbol dibutyrate receptors. These actions of A23187 were abolished in the presence of EGTA or TMB-8, confirming a dependence on Ca²⁺.

【 授权许可】

Unknown