Stimulation by epinephrine of in vivo phosphorylation and inactivation of acetyl coenzyme A carboxylase of rat epididymal adipose tissue.
Stimulation by epinephrine of in vivo phosphorylation and inactivation of acetyl coenzyme A carboxylase of rat epididymal adipose tissue.
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肾上腺素刺激大鼠附睾脂肪组织的体内磷酸化和乙酰辅酶 A 羧化酶失活。
DOI：
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发表时间：
1979
影响因子：
4.8
通讯作者：
K. H. Kim
中科院分区：
文献类型：
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作者：
K. H. Lee;K. H. Kim
将无机32 P腹腔注射到大鼠中导致32 P掺入乙酰辅酶A羧化酶而不使酶失活。给予肾上腺素刺激32 P掺入并导致酶失活。附睾脂肪组织与无机~（32）P的孵育也导致~（32）P掺入羧化酶。此32 P掺入在3 h内达到最大水平，并且对羧化酶活性没有影响。在最大磷酸化时间（3 h）给予肾上腺素导致羧化酶进一步磷酸化和失活。普萘洛尔是一种抑制肾上腺素作用的β-肾上腺素能阻滞剂，可阻断肾上腺素刺激的磷酸化和羧化酶的失活。然而，普萘洛尔对与酶失活无关的磷酸化组分没有影响。这些结果表明，羧化酶的磷酸化在体内发生在两个不同的位点，其中只有一个导致酶失活。与酶失活相关的磷酸化位点是神经系统控制的。
Intraperitoneal injection of inorganic 32P into rats results in the incorporation of 32P into acetyl-CoA carboxylase without inactivation of the enzyme. Administration of epinephrine stimulates 32P incorporation and results in enzyme inactivation. Incubation of epididymal fat tissues with inorganic 32P also results in incorporation of 32P into carboxylase. This 32P incorporation reaches a maximum level in 3 h and it has no effect on carboxylase activity. Administration of epinephrine at the time of maximum phosphorylation (3 h) results in further phosphorylation and inactivation of carboxylase. Propranolol, a beta-adrenergic blocking agent which inhibits epinephrine action, blocks both the epinephrine-stimulated phosphorylation and the inactivation of the carboxylase. However, propranolol has no effect on that component of the phosphorylation which is unrelated to enzyme inactivation. These results establish that phosphorylation of carboxylase occurs in vivo at two different sites, only one of which results in enzyme inactivation. The phosphorylation site associated with enzyme inactivation is hormonally controlled.