Insulin-dependent and insulin-independent low Km cyclic AMP phosphodiesterase from rat adipose tissue.
نویسندگان
چکیده
Chromatographic analysis of a soluble extract of rat adipose tissue on DEAE-Sephacel resolves four distinct peaks of 3':5'-nucleotide phosphodiesterase (EC 3.1.4.17) activity. Kinetic investigation indicates that two of these fractions have a high affinity for cyclic AMP and show negative cooperative kinetic behavior at high substrate concentration. They differ in the degree of inhibition by cyclic GMP and in their response to insulin. If rat epididymal fat pads are incubated with insulin prior to homogenization, only one of the low Km cyclic AMP phosphodiesterase forms is stimulated.
منابع مشابه
Controle of the metabolism and lipolytic effects of cyclic 3',5'-adenosine monophosphate in adipose tissue by insulin, methyl xanthines, and nicotinic acid.
1. We have tested the hypothesis that insulin might decrease the levels of cyclic AMP (CAMP) in rat epididymal adipose tissue by stimulating the activity of a CAMP phosphodiesterase. 2. Dibutyryl cyclic AMP (DBcAMP) was comparable to CAMP as a substrate for CAMP phosphodiesterase of adipose tissue; the hydrolysis of both cyclic nucleotides was inhibited by theophylline. 3. DBcAMP, but not CAMP,...
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ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 257 10 شماره
صفحات -
تاریخ انتشار 1982