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The effect of glucose, insulin and noradrenaline on lipolysis, and on the concentrations of adenosine 3':5'-cyclic monophosphate and adenosine 5'-triphosphate in adipose tissue.

ABSTRACT: Glycerol release and tissue concentrations of ATP and cyclic AMP were followed during the incubation of adipose tissue with or without glucose, insulin and noradrenaline. Glucose plus insulin or, to a lesser extent, glucose alone increased the accumulation of glycerol during incubations both with and without noradrenaline by slowing the decline in the rate of glycerol release with time. Insulin alone decreased the accumulation by accelerating the fall in glycerol release. In the absence of noradrenaline, ATP and cyclic AMP concentrations were not significantly affected by insulin or glucose. With noradrenaline or noradrenaline plus insulin the ATP concentration gradually fell. With noradrenaline plus glucose the ATP concentration fell rapidly and then stabilized, or, if insulin was also present, returned to the control value. In the presence of noradrenaline, the concentration of cyclic AMP rose during the first 20min and then fell. Insulin lowered the peak concentration of cyclic AMP, but glucose had no effect either on the peak value or the fall in the concentration of the nucleotide. The increase and fall in the concentration of cyclic AMP with noradrenaline or noradrenaline plus insulin bore similarities to the increase and decline in the lipolytic rate in incubations without glucose. It is proposed that glucose stimulates ATP production by furnishing glycerol 1-phosphate and thus removing free fatty acids, but that it can influence lipolysis by a mechanism which is distinct from any which is mediated by free fatty acids, possibly by inhibiting the inactivation of the lipase.

SUBMITTER: Knight BL

PROVIDER: S-EPMC1177561 | biostudies-other | 1973 Jan

REPOSITORIES: biostudies-other

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An effect of insulin on adipose-tissue adenosine 3':5'-cyclic monophosphate phosphodiesterase.

Project description:1. 3':5'-Cyclic nucleotide phosphodiesterase activity was measured in homogenates prepared from epididymal fat-pads and isolated fat-cells incubated in the absence and presence of insulin. 2. Homogenates of insulin-treated tissues showed an increase in phosphodiesterase activity compared with controls. No effect of insulin was observed when the hormone was added directly to homogenates. 3. There was kinetic evidence for the presence of two 3':5'-cyclic nucleotide phosphodiesterases in adipose tissue. Insulin raised the maximal velocity of the low-K(m) enzyme and lowered the K(m) of the higher-K(m) enzyme. 4. It is suggested that the effect of insulin on adipose tissue phosphodiesterase accounts for the ability of this hormone to lower cyclic-AMP concentration in the tissue.

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Does cyclic guanosine monophosphate mediate noradrenaline-induced inhibition of islet insulin secretion stimulated by glucose and palmitate?

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Gene expression in undifferentiated or cyclic adenosine monophosphate-exposed BeWo trophoblast cells

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2015-08-01 | GSE66840 | GEO

"cAMP sponge": a buffer for cyclic adenosine 3', 5'-monophosphate.

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Gene expression in undifferentiated or cyclic adenosine monophosphate-exposed BeWo trophoblast cells

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A DNA Aptamer for Cyclic Adenosine Monophosphate that Shows Adaptive Recognition.

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Stimulation of glucose transport in rat adipocytes by insulin, adenosine, nicotinic acid and hydrogen peroxide. Role of adenosine 3':5'-cyclic monophosphate.

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