REVERSIBLE INACTIVATION BY NORADRENALINE OF LONG-CHAIN FATTY ACYL-COA SYNTHETASE IN RAT ADIPOCYTES
REVERSIBLE INACTIVATION BY NORADRENALINE OF LONG-CHAIN FATTY ACYL-COA SYNTHETASE IN RAT ADIPOCYTES
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DOI：
10.1042/bj2260275
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发表时间：
1985-01-01
影响因子：
4.1
通讯作者：
SAGGERSON, ED
中科院分区：
文献类型：
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作者：
HALL, M;SAGGERSON, ED
将大鼠脂肪细胞与刺激脂肪分解的相同范围的去甲肾上腺素[去甲肾上腺素]浓度一起孵育，导致脂肪酰辅酶A合成酶的活性快速稳定地降低。促肾上腺皮质激素、胰高血糖素和二丁酰环磷酸腺苷也降低了该酶的活性。去甲肾上腺素对于该酶的 3 种底物的作用在很宽的浓度范围内都很明显。描述了一种使用 (1,N6-乙烯)-CoA 的脂肪酰基辅酶 A 合成酶的新型荧光测定法。 去甲肾上腺素的作用不会因为在均质化缓冲液中加入白蛋白而被消除，而是通过亚细胞分级分离和微粒体（微粒体级分）的分离而持续存在，甚至在用 Triton X-100 处理微粒体后仍然存在。通过随后添加胰岛素或普萘洛尔，去甲肾上腺素的作用在细胞内迅速逆转。在均质缓冲液中加入氟化物并没有改变观察到的去甲肾上腺素的作用。向脂肪细胞微粒体添加cAMP依赖性蛋白激酶引起[γ-32P]ATP对微粒体蛋白的大量磷酸化，但不影响脂酰辅酶A合成酶的活性。
Incubation of rat adipocytes with the same range of noradrenaline [norepinephrine] concentrations that stimulate lipolysis caused a rapid and stable decrease in the activity of fatty acyl-CoA synthetase. Corticotropin, glucagon and dibutyryl cAMP also decreased the activity of the enzyme. The effect of noradrenaline was apparent over a wide range of concentrations for the 3 substrates of the enzyme. A novel fluorescence assay of fatty acyl-CoA synthetase using (1,N6-etheno)-CoA is described. The effect of noradrenaline was not abolished by inclusion of albumin in homogenization buffers, persisted through subcellular fractionation and isolation of microsomes (microsomal fractions) and even survived treatment of microsomes with Triton X-100. The effect of noradrenaline was rapidly reversed within cells by the subsequent addition of insulin or propranolol. The inclusion of fluoride in homogenization buffers did not alter the observed effect of noradrenaline. Additions of cAMP-dependent protein kinase to adipocyte microsomes caused considerable phosphorylation of microsomal protein by [.gamma.-32P]ATP, but did not affect the activity of fatty acyl-CoA synthetase.