FORMATION OF ADENOSINE-3',5'-PHOSPHATE (CYCLIC ADENYLATE) AND ITS RELATION TO THE ACTION OF SEVERAL NEUROHORMONES OR HORMONES

A cyclic nucleotide, adenosine-3', 5'-phosphate, or cyclic adenylate was found in animal tissues as a result of studies on the mechanism of action of sympathomimetic amines and glucagon (Rail & Sutherland 1958; Sutherland & Rall 1958). This nucleotide has been prepared chemically by Lipkin and co-workers who have recently published studies on the chemical properties of this cyclic nucleotide (Lipkin et al. 1959). Earlier studies had shown that the effect of adrenaline in homogenates, leading to increased levels of active phosphorylase, was lost if a particulate fraction was removed by centrifugation. When the particulate fraction was incubated with adenosine triphosphate and magnesium ions, the heat stable cyclic nucleotide was formed. The cyclic nucleotide increased the formation of active phosphorylase in supernatant fractions of tissue preparations where adrenaline and glucagon did not; adrenaline and glucagon stimulated the formation of cyclic adenylate. In other words, the effect of adrenaline and glucagon on