Miller J C, Kowal C N
Biochem Pharmacol. 1983 Jul 15;32(14):2237-41. doi: 10.1016/0006-2952(83)90232-0.
The metabolism of phosphatidylinositol and phosphatidate was studied in isolated rat parotid cells, incubated in a physiological buffer containing [32P]phosphate or [3H]glycerol. Carbamylcholine and epinephrine stimulated 32P incorporation into both of these phospholipids, causing their half-maximal effects at 2 and 0.8 microM respectively. The former concentration is much lower than that anticipated from binding studies. The Hill coefficients for carbamylcholine activation of 32P incorporation were 0.61 +/- 0.05 for phosphatidate and 0.64 +/- 0.05 for phosphatidylinositol. Pentobarbital (0.58 mM) inhibited the increased 32P incorporation caused by 5 microM carbamylcholine but not 100 microM carbamylcholine. Pentobarbital inhibited the incorporation of 3H equally in the presence and absence of epinephrine, indicating that the effect of pentobarbital on 32P incorporation is on turnover and not on de novo synthesis. Veratridine (200 microM) had no effect on phospholipid metabolism in the presence and absence of either carbamylcholine or epinephrine, which contrasts with our previous findings in synaptosomes [J.C. Miller and I. Leung, Biochem. J. 178, 9 (1979)].
在含有[32P]磷酸盐或[3H]甘油的生理缓冲液中孵育的离体大鼠腮腺细胞中，研究了磷脂酰肌醇和磷脂酸的代谢。氨甲酰胆碱和肾上腺素刺激32P掺入这两种磷脂中，它们的半数最大效应分别在2微摩尔和0.8微摩尔时出现。前一浓度远低于结合研究预期的浓度。氨甲酰胆碱激活32P掺入磷脂酸的希尔系数为0.61±0.05，激活磷脂酰肌醇的希尔系数为0.64±0.05。戊巴比妥（0.58毫摩尔）抑制了5微摩尔氨甲酰胆碱引起的32P掺入增加，但不抑制100微摩尔氨甲酰胆碱引起的增加。戊巴比妥在有和没有肾上腺素存在的情况下均同等程度地抑制3H的掺入，这表明戊巴比妥对32P掺入的影响是对周转的影响，而不是对从头合成的影响。在有或没有氨甲酰胆碱或肾上腺素存在的情况下，藜芦碱（200微摩尔）对磷脂代谢均无影响，这与我们之前在突触体中的发现形成对比[J.C.米勒和I.梁，《生物化学杂志》178, 9 (1979)]。
