Action du dibutyryl 3′5′‐AMP cyclique sur la lipogenese et la neoglucogenese chez la souris vivante

Abstract

N6-2'Gdibutyryl cyclic AMP stimulates glycogenolysis and inhibits fatty acid synthesis in rat liver in vivo but has little effect on gluconeogenesis. In adipose tissue: it enhances lipogenesis and glycogenesis. These last effects can be explained by an increase of insulin release.

Effect of dibutyryl cAMP on the enzymes of fatty acid synthesis and of glycogen metabolism

“…The radioactivity of the applied labeled precursor would be diluted by acetyl-CoA through glycogen degradation. This last assumption is supported by the following facts: first, in vivo, the inhibitory effect appears only in liver and not in the carcass or in adipose tissue with cAMP or its dibutyryl derivative [3] or with cGMP [4] ; second, the two successive administrations of db cAMP failed to inhibit the liver fatty acid synthesis in vivo. Thus when the animals have been deprived of glycogen by a first injection of db cAMP, the inhibitory effect of this compound disappears.…”

“…Inhibition of fatty acid synthesis by 3',5'-cAMP or its dibutyryl derivative (db cAMP) has been described in liver [1][2][3][4][5], but no inhibitory action was detectable in adipose tissue [3,4]. A stimulation of insulin release by this nucleotide has been suggested to explain this last result.…”

“…A stimulation of insulin release by this nucleotide has been suggested to explain this last result. An other explanation could be that the hepatic fatty acids synthesis inhibition was only apparent and due to a dilution effect caused by glycogenolysis induced by this nucleotide [3]. It was of interest, therefore, to determine whether 3',5'-cAMP acts directly on the liver fatty acid synthesis either by repression of the synthesis of the corresponding enzymes or by decreasing their activity.…”