Enhancement of arachidonic acid liberation by protein kinase C activator is partially dependent on extracellular Na+ in rabbit platelets

FEBS Letters

Akibaaf, Satoshi¹  Fujii, Tatsuzo¹  Sato, Takashi¹ 

[1] Department of Biochemistry, Kyoto Pharmaceutical University, Kyoto 607, Japan

关键词: Arachidonic acid liberation;    Protein kinase C;    Na+/H+ exchange;    Intracellular alkalinization;    (Rabbit platelet);    PMA;    4β-phorbol 12-myristate 13-acetate;    DOG;    dioctanoylglycerol;    GTPγS;    guanosine 5′-O-[3-thiotriphosphate];    G-protein;    guanine-nucleotide-binding protein;   

DOI  :  10.1016/0014-5793(89)81003-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

In [³H]arachidonic acid-labeled rabbit platelets, pretreatment with phorbol 12-myristate 13-acetate (20 nM) or dioctanoylglycerol (20 μM) enhanced [³H]arachidonic acid liberation induced by low concentration of A23187 (150 nM). When extracellular Na²⁺ was replaced with N-methyl-D-glucamine, the enhancement is reduced by about 50%. Similar synergistic enhancement of the liberation was obtained by using monensin (2–10 μM) or NH₄Cl (5–20 mM) in place of protein kinase C activator in combination with A23187. The guanosine 5′-O-[3-thiotriphosphate] (100 μM)-induced liberation was also enhanced by a rise of extracellular pH (pH 7.0–7.8) in saponin-permeabilized platelets. These results suggest that the enhancement of arachidonic acid liberation by protein kinase C may partially be mediated by intracellular alkalinization in rabbit platelets.

【 授权许可】

Unknown