par Chatelain, Pierre ;Berliner, Carol ;Ruysschaert, Jean Marie ;Jaffe, Jacob
Référence Biochimica et biophysica acta, 419, 3, page (540-546)
Publication Publié, 1976-02
Référence Biochimica et biophysica acta, 419, 3, page (540-546)
Publication Publié, 1976-02
Article révisé par les pairs
Résumé : | AC-3579 (2-N-methylpiperazinomethyl-1,3-diazafluoranthen 1-oxide) produces in rat hepatocytes a hypertrophy of the endoplasmic reticulum. Two possibilities that can explain this phenomenon are (1) that AC-3579 inactivates the phospholipases, and (2) that an AC-3579-lipid interaction hinders the enzymic activity. To demonstrate these hypotheses, a physicochemical model of biological membrane, the lipid-water interface, has been used. Dipalmitoyl DL-alpha-phosphatidyl-choline was spread at the air-water interface, the enzymes (phospholipase A or phospholipase C) dissolved in the aqueous phase. The enzymic reaction was first studied with and without AC-3579 dissolved in the aqueous phase; no enzymic inactivation was observed. However an AC-3579-lipid complex completely inhibited the enzymic reaction in the case of phospholipase A. An explanation is given in terms of steric hindrance to the enzyme-substrate. |