Marin-Cao D, Alvarez Chiva V, Mato J M
Biochem J. 1983 Dec 15;216(3):675-80. doi: 10.1042/bj2160675.
Changes in isoprenaline-sensitive phospholipid methyltransferase were studied in hepatocytes isolated from juvenile, mature and adrenalectomized rats. Isoprenaline produced greater stimulation of cyclic AMP accumulation in juvenile and mature adrenalectomized rats than in mature animals. Similarly, isoprenaline stimulated phospholipid methyltransferase in juvenile and mature adrenalectomized rats but had no effect in mature animals. Isoprenaline-mediated activation of phospholipid methyltransferase in adrenalectomized rats was time- and dose-dependent. In hepatocytes isolated from adrenalectomized rats incubated with [Me-3H]methionine or [3H]-ethanolamine the addition of isoprenaline increased the amount of radioactivity incorporated into phosphatidylcholine. The activation by isoprenaline of phospholipid methyltransferase was abolished by the beta-blocker propranolol and by insulin. These results indicate that rat liver the occupation of functional beta-receptors causes a stimulation of phospholipid methylation. It is suggested that, as reported previously, cyclic AMP activates phospholipid methyltransferase.
研究了从幼年、成年和去肾上腺大鼠分离的肝细胞中异丙肾上腺素敏感的磷脂甲基转移酶的变化。与成年动物相比，异丙肾上腺素对幼年和成年去肾上腺大鼠的环磷酸腺苷积累产生更大的刺激作用。同样，异丙肾上腺素刺激幼年和成年去肾上腺大鼠的磷脂甲基转移酶，但对成年动物没有影响。异丙肾上腺素介导的去肾上腺大鼠磷脂甲基转移酶的激活具有时间和剂量依赖性。在用[甲基-³H]甲硫氨酸或[³H]-乙醇胺孵育的去肾上腺大鼠分离的肝细胞中，加入异丙肾上腺素会增加掺入磷脂酰胆碱的放射性量。β受体阻滞剂普萘洛尔和胰岛素消除了异丙肾上腺素对磷脂甲基转移酶的激活作用。这些结果表明，在大鼠肝脏中，功能性β受体的占据会导致磷脂甲基化的刺激。有人提出，如先前报道的那样，环磷酸腺苷激活磷脂甲基转移酶。
