An assay for measuring 3’,5’-cyclic nucleotide phosphodiesterase activity over a wide range of substrate concentrations has been described. The ratio of cyclic adenosine 3’,5’monophosphate (cyclic AMP) to cyclic guanosine 3’,5’monophosphate (cyclic GMP) hydrolysis varied several fold among crude subcellular fractions from bovine and rat heart when measured at micromolar but not millimolar subst...

Escherichia coli alkaline phosphatase (AP) is a proficient phosphomonoesterase with two Zn(2+) ions in its active site. Sequence homology suggests a distant evolutionary relationship between AP and alkaline phosphodiesterase/nucleotide pyrophosphatase, with conservation of the catalytic metal ions. Furthermore, many other phosphodiesterases, although not evolutionarily related, have a similar a...

An anti-calmodulin monoclonal antibody having an absolute requirement for Ca2+ has been produced from mice immunized with a mixture of calmodulin and calmodulin-binding proteins. Radioimmune assays were developed for the determination of its specificity. the epitope for this antibody resides on the COOH-terminal half of the mammalian protein. Plant calmodulin or troponin C had little reactivity...

A 3'-deoxy-3'-C-methylenephosphonate modified diribonucleotide is highly resistant to degradation by spleen phosphodiesterase and not cleaved at all by snake venom phosphodiesterase. The most remarkable finding is that, despite the fact that both the vicinal 2-hydroxy nucleophile and the 5'-oxyanion leaving group are intact, the 3'-methylenephosponate RNA modification is also highly resistant t...

Citation: Nydegger C, Martinelli C, Di Marco F, Bulfamante G, von Segesser L, Tozzi P, Samaja M and Milano G (2018) Phosphodiesterase-5 Inhibition Alleviates Pulmonary Hypertension and Basal Lamina Thickening in Rats Challenged by Chronic Hypoxia. Front. Physiol. 9:289. doi: 10.3389/fphys.2018.00289 Phosphodiesterase-5 Inhibition Alleviates Pulmonary Hypertension and Basal Lamina Thickening in ...

A single specifically labeled protein (Mr = 42,000) is found when Dictyostelium discoideum crude membrane (ghost) preparations are photoaffinity-labeled with either [32P]8N3-cAMP or [32P]8N3-AMP. With the CAMP reagent, there is a close correlation between the labeling of this protein and the membrane phosphodiesterase activity. During cell differentiation the developmental time courkes of the p...

PURPOSE Phosphodiesterase type 5 inhibitors were recently introduced as a new treatment option for men with lower urinary tract symptoms. Safety and clinical effectiveness are well documented but the mode of action is still unclear. We determined and compared the expression of phosphodiesterase type 5 in the spinal cord of normal (sham operated) rats and rats with partial urethral obstruction i...

1. We have tested the hypothesis that insulin might decrease the levels of cyclic AMP (CAMP) in rat epididymal adipose tissue by stimulating the activity of a CAMP phosphodiesterase. 2. Dibutyryl cyclic AMP (DBcAMP) was comparable to CAMP as a substrate for CAMP phosphodiesterase of adipose tissue; the hydrolysis of both cyclic nucleotides was inhibited by theophylline. 3. DBcAMP, but not CAMP,...