We investigated the roles of cyclic GMP and cyclic AMP in the inhibition of rabbit platelet aggregation and degranulation by two nitrovasodilators, sodium nitroprusside (SNP) and 3-morpholinosydnonimine (SIN-1; the active metabolite of molsidomine), with particular reference to the synergistic interaction of these drugs with prostaglandin E1 (PGE1). Changes in platelet cyclic [3H]GMP and cyclic...

Cyclic adenosine 3’,5’-monophosphate (cyclic AMP) increases the differential rate of synthesis of @-galactosidase in Escherichia coli made permeable by treatment with t&(hydroxymethyl)aminomethane and ethylenediaminetetraacetic acid. In normal, growing cells, cyclic AMP overcomes the transient repression of /3-galactosidase by glucose. A half-maximal effect of cyclic AMP occurs at about 7 x 10-...

The effect of adenosine on the increase in cardiac cyclic adenosine 3',5'-monophosphate (cyclic AMP) concentration and glycogen phosphorylase activity produced by isoproterenol was investigated. Slices of rat ventricular myocardium 0.5 mm thick weighing 15-20 mg were cut, washed, and incubated at 37 °C in physiological saline gassed with either O2 (oxygenated) or N2 (anoxia). The concentration ...

The binding of adenosine cyclic 3':5'-monophosphate (cyclic AMP) with soluble (100,000 X g supernatant), pellet, and total homogenate proteins from cyclic AMP-induced "differentiated" mouse neuroblastoma cells increased by about two-fold. The extent of binding with soluble proteins was higher than that with pellet proteins. The binding of cyclic AMP with soluble proteins from 5'-adenosine monop...

Cyclic adenosine 3’,5’-monophosphate (cyclic AMP) increases the differential rate of synthesis of @-galactosidase in Escherichia coli made permeable by treatment with t&(hydroxymethyl)aminomethane and ethylenediaminetetraacetic acid. In normal, growing cells, cyclic AMP overcomes the transient repression of /3-galactosidase by glucose. A half-maximal effect of cyclic AMP occurs at about 7 x 10-...

We used embryonic chick pelvic cartilage as a model to study the mechanism by which cyclic AMP increases RNA synthesis. Isolated nuclei were incubated with [32P]-8-azidoadenosine 3,5'-monophosphate ([32P]N3cAMP) with no resultant specific nuclear binding. However, in the presence of cytosol proteins, nuclear binding of [32P]N3cAMP was demonstrable that was specific, time dependent, and dependen...

Previous studies have shown that exogenous dibutyryl cyclic AMP inhibits the uptake of uridine, leucine, and 2-deoxyglucose by cultured mouse fibroblasts. 3':5'-cyclic GMP is shown here to counteract these inhibitory effects as well as the inhibition of precursor transport and leucine incorporation into proteins produced by prostaglandin E(1). We conclude, therefore, that cyclic GMP antagonizes...

The adenine nucleotides, 5'-AMP and 3',5'-cyclic AMP block L cells in the S-phase of the cell cycle. The intracellular level of cyclic AMP is reduced after incubation of cells with 5'-AMP, and rates of uridine transport are increased after incubation with either 5'-AMP or cyclic AMP. On the contrary, cyclic AMP levels are increased and uridine transport decreased in cells treated with an inhibi...

KUROKAWA, KIYOSHI, AND SHAUL G. MASSRY. Interaction between catecholamines and vasopressin on renal medullary cyclic AMP of rat. Am. J. Physiol. 225(4) : 825-829. 1973.-The effects of catecholamines, alphaand beta-adrenergic blockers, and the interaction between these agents and vasopressin on cyclic AMP concentration in suspensions of isolated cortical and medullary tubules of rat kidney were ...

The unicellular eukaryote Tetrahymena pyriformis secretes significant amounts of cyclic AMP into its external medium. Cells transferred from growth medium into any of the following three different non-nutrient media: (a) 5 mM phosphate buffer containing 47 mM NaCl and 1 mM MgSO4, (b) 10 mM Tris, or (c) 1.3 mM Tris containing 1 mM citrate and 1 mM Ca(OH)2, released to the outside almost 60--80% ...