The calmodulin-activated cyclic nucleotide phosphodiesterase from bovine brain cortex has been extensively purified by two methods, both of which yield preparations containing a single major polypeptide of 58,000 daltons as judged by gel electrophoresis under denaturing conditions. The preparations have similar specific activities in the presence of calmodulin (plus Ca2+) but differ in the degr...

Changes in levels of the newly discovered cytidine 3':5'-cyclic monophosphate (cyclic CMP) phosphodiesterase in some representative tissues (cerebral cortex, kidney, intestine, liver, heart, and lung) of guinea pigs from various developmental stages (fetus, neonate, pup, and adult) were studied and compared with those of cyclic AMP and cyclic GMP phosphodiesterases in the same tissues. It was o...

The activity of cyclic 3 :5 -nucleotide phosphodiesterase was measured in thymocytes and splenic lympho cytes of AKR mice of various ages. Concurrently, the cell distribution profiles of these cell populations were studied by laser cytometric analysis. The results indicate that lymphocyte and thymocyte populations from young, con trol animals are relatively homogeneous with respect to cell size...

INTRODUCTION Pulmonary arterial hypertension (PAH), characterized by increased pulmonary artery pressures in the absence of elevated pulmonary venous pressures, is a progressive disease associated with reduced exercise capacity and increased mortality risk. Current treatments for PAH include nonspecific vasodilators, prostacyclin and related analogs, and endothelin receptor antagonists. Since p...

BACKGROUND AND PURPOSE In vitro evidence gathered from extracerebral conductance vessels suggests interaction between the endothelium-derived relaxing factor for acetylcholine (EDRFACh) and cyclic nucleotide action in vascular smooth muscle. The purpose of this study was to examine this interaction in vivo in pial arterioles. As had been done in vitro, we used phosphodiesterase inhibitors that ...

The functional influence of cell proteoglycan (PG) undersulfation on estradiol synthesis by immature rat Sertoli cell cultures was investigated by using sodium chlorate, an inhibitor of the active sulfate donor for sulfotransferases. The addition of sodium chlorate to 20-day-old rat Sertoli cell cultures abolished [35S]-sulfate incorporation into neosynthesized PG and consequently reduced the r...

Glycerophosphocholine (GroPCho) is a diester that accumulates in different physiological processes leading to phospholipid remodeling. However, very little is known about its metabolism in higher plant cells. (31)P-Nuclear magnetic resonance spectroscopy and biochemical analyses performed on carrot (Daucus carota) cells fed with GroPCho revealed the existence of an extracellular GroPCho phospho...

The behaviour of cyclic-3',5'-AMP phosphodiesterase has been studied in the presence of psoralen, 8-methoxy-psoralen (8-MOP), 4,5',8-trimethylpsoralen (TMP) (usually used in PUVA therapy), 4,6,4'-trimethylangelicin (TMA) and khellin recently proposed for the same therapeutical use. TMP and TMA exhibit a significant inhibitory effect on cyclic AMP phosphodiesterase; a light inhibition is produce...

Inhibition of 3':5'-cyclic-AMP-5'-nucleotidohydrolase (EC 3.1.4.17) type II (cAMP-phosphodiesterase) by sodium molybdate was studied: While determination of inorganic phosphate and 5'-ribonucleotide phosphohydrolase (5'-nucleotidase) (EC 3.1.3.5) activity was not disturbed by sodium molybdate in concentrations up to 10 mM, cAMP-phosphodiesterase was inhibited by millimolar concentrations of mol...