Kelly K L, Gutierrez G, Martin A
University of Pennsylvania School of Medicine, Philadelphia 19104.
Biochem J. 1988 Oct 15;255(2):693-8.
The effect of both lipolytic and antilipolytic hormones on the turnover of phosphatidylcholine in freshly isolated rat adipocytes was investigated. Treatment of adipocytes with agonists such as glucagon or isoprenaline that stimulate lipolysis through a cyclic AMP-dependent mechanism caused an increase in the incorporation of [Me-3H]choline into phosphatidylcholine. Pulse-chase studies indicated that the stimulation was due to an increase in the conversion of choline into phosphatidylcholine, which was both time- and dose-dependent. The stimulatory effect of isoprenaline was inhibited in a dose-dependent manner by oxytocin or insulin. Oxytocin inhibited the incorporation of [Me-3H]choline into phosphatidylcholine in both the presence and the absence of isoprenaline, whereas in the absence of isoprenaline insulin increased the incorporation of [Me-3H]choline into phosphatidylcholine. The effects of isoprenaline, oxytocin and insulin on the incorporation of [3H]choline into phosphatidylcholine were paralleled by changes in the activity of CTP:phosphocholine cytidylyltransferase.
研究了脂解激素和抗脂解激素对新鲜分离的大鼠脂肪细胞中磷脂酰胆碱周转的影响。用胰高血糖素或异丙肾上腺素等激动剂处理脂肪细胞，这些激动剂通过环磷酸腺苷（cAMP）依赖性机制刺激脂解，导致[甲基-3H]胆碱掺入磷脂酰胆碱增加。脉冲追踪研究表明，这种刺激是由于胆碱转化为磷脂酰胆碱的增加，这是时间和剂量依赖性的。异丙肾上腺素的刺激作用被催产素或胰岛素以剂量依赖性方式抑制。无论有无异丙肾上腺素，催产素均抑制[甲基-3H]胆碱掺入磷脂酰胆碱，而在无异丙肾上腺素时，胰岛素增加[甲基-3H]胆碱掺入磷脂酰胆碱。异丙肾上腺素、催产素和胰岛素对[3H]胆碱掺入磷脂酰胆碱的影响与CTP：磷酸胆碱胞苷转移酶活性的变化平行。
