Various Subtypes of Phosphodiesterase Inhibitors Differentially Regulate Pulmonary Vein and Sinoatrial Node Electrical Activities
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Cardioactive Agents : Metoprolol, Sotalol and Milrinone. Influence of Myocardial Content and Systolic Interval
3Õ' î'qt ACUTE HAEMODYNAMIC EFFECTS OF THREE CARDIOACTIVE AGENTS : METOPROLOL, SOTALOL AND MILRINONE. INFLUENCE OF MYOCARDIAL CONTENT AND SYSTOLIC INTERVAL. by Rebecca Helen Ritchie, B.Sc (Hons) A thesis submitted for the degree of Doctor of Philosophy ln The University of Adelaide (Faculty of Medicine) February 1994 Department of Medicine (Cardiology Unit, The Queen Elizabeth Hospital) The University of Adelaide Adelaide, SA, 5000. ll ¡ r -tL',. r,0';(', /1L.)/'t :.: 1 TABLE OF CONTENTS Table of contents 1 Declaration vtl Acknowledgements v111 Publications and communications to learned societies in support of thesis D( Summary xl Chapter 1: General Introduction 1 1.1 Overview 2 1.2 Acute effeots of cardioactive drugs 3 1.2.1 Drug effects 4 l.2.2Determnants of drug effects 5 1.3 Myocardial drug gPtake of cardioactive agents 8 1.3.1 Methods of assessment in humans invívo 9 1.3.2 Results of previous studies 10 1.4Influence of cardioactive drugs on contractile state 11 1.4. 1 Conventional indices 11 I.4.2 The staircase phenomenon t2 1.4.3 The mechanical restitution curve t2 1.5 The present study t4 1.5.1 Current relevant knowledge of the acute haemodynamic effects of the cardioactive drugs under investigation r4 1.5.1.1 Metoprolol 15 1.5.1.2 Sotalol 28 1.5.1.3 Milrinone 43 1.5.2 Cunent relevant knowledge of the short-term pharmacokinetics of the cardioactive drugs under investigation 59 1.5.2.1Metoprolol 59 1.5.2.2 Sotalol 7I ll 1.5.2.3 Milrinone 78 1.5.3 Current relevant knowledge of the potential for rate-dependence of the effects of these -
Theophylline and Selective PDE Inhibitors As Bronchodilators and Smooth Muscle Relaxants
Eur Respir J, 1995, 8, 637–642 Copyright ERS Journals Ltd 1995 DOI: 10.1183/09031936.95.08040637 European Respiratory Journal Printed in UK - all rights reserved ISSN 0903 - 1936 SERIES 'THEOPHYLLINE AND PHOSPHODIESTERASE INHIBITORS' Edited by M. Aubier and P.J. Barnes Theophylline and selective PDE inhibitors as bronchodilators and smooth muscle relaxants K.F. Rabe, H. Magnussen, G. Dent Theophylline and selective PDE inhibitors as bronchodilators and smooth muscle relaxants. Krankenhaus Grosshansdorf, Zentrum für K.F. Rabe, H. Magnussen, G. Dent. ERS Journals Ltd 1995. Pneumologie und Thoraxchirurgie, LVA ABSTRACT: In addition to its emerging immunomodulatory properties, theophy- Hamburg, Grosshansdorf, Germany. lline is a bronchodilator and also decreases mean pulmonary arterial pressure in vivo. The mechanism of action of this drug remains controversial; adenosine Correspondence: K.F. Rabe Krankenhaus Grosshansdorf antagonism, phosphodiesterase (PDE) inhibition and other actions have been advanced Wöhrendamm 80 to explain its effectiveness in asthma. Cyclic adenosine monophosphate (AMP) and D-22927 Grosshansdorf cyclic guanosine monophosphate (GMP) are involved in the regulation of smooth Germany muscle tone, and the breakdown of these nucleotides is catalysed by multiple PDE isoenzymes. The PDE isoenzymes present in human bronchus and pulmonary artery Keywords: Bronchi have been identified, and the pharmacological actions of inhibitors of these enzy- 3',5'-cyclic-nucleotide phosphodiesterase mes have been investigated. phosphodiesterase inhibitors Human bronchus and pulmonary arteries are relaxed by theophylline and by pulmonary artery selective inhibitors of PDE III, while PDE IV inhibitors also relax precontracted smooth muscle theophylline bronchus and PDE V/I inhibitors relax pulmonary artery. There appears to be some synergy between inhibitors of PDE III and PDE IV in relaxing bronchus, and Received: February 1 1995 a pronounced synergy between PDE III and PDE V inhibitors in relaxing pulmon- Accepted for publication February 1 1995 ary artery. -
Looking for New Classes of Bronchodilators
REVIEW BRONCHODILATORS The future of bronchodilation: looking for new classes of bronchodilators Mario Cazzola1, Paola Rogliani 1 and Maria Gabriella Matera2 Affiliations: 1Dept of Experimental Medicine, University of Rome Tor Vergata, Rome, Italy. 2Dept of Experimental Medicine, University of Campania “Luigi Vanvitelli”, Naples, Italy. Correspondence: Mario Cazzola, Dept of Experimental Medicine, University of Rome Tor Vergata, Via Montpellier 1, Rome, 00133, Italy. E-mail: [email protected] @ERSpublications There is a real interest among researchers and the pharmaceutical industry in developing novel bronchodilators. There are several new opportunities; however, they are mostly in a preclinical phase. They could better optimise bronchodilation. http://bit.ly/2lW1q39 Cite this article as: Cazzola M, Rogliani P, Matera MG. The future of bronchodilation: looking for new classes of bronchodilators. Eur Respir Rev 2019; 28: 190095 [https://doi.org/10.1183/16000617.0095-2019]. ABSTRACT Available bronchodilators can satisfy many of the needs of patients suffering from airway disorders, but they often do not relieve symptoms and their long-term use raises safety concerns. Therefore, there is interest in developing new classes that could help to overcome the limits that characterise the existing classes. At least nine potential new classes of bronchodilators have been identified: 1) selective phosphodiesterase inhibitors; 2) bitter-taste receptor agonists; 3) E-prostanoid receptor 4 agonists; 4) Rho kinase inhibitors; 5) calcilytics; 6) agonists of peroxisome proliferator-activated receptor-γ; 7) agonists of relaxin receptor 1; 8) soluble guanylyl cyclase activators; and 9) pepducins. They are under consideration, but they are mostly in a preclinical phase and, consequently, we still do not know which classes will actually be developed for clinical use and whether it will be proven that a possible clinical benefit outweighs the impact of any adverse effect. -
Analyses of PDE-Regulated Phosphoproteomes Reveal Unique and Specific Camp-Signaling Modules in T Cells
Analyses of PDE-regulated phosphoproteomes reveal unique and specific cAMP-signaling modules in T cells Michael-Claude G. Beltejara, Ho-Tak Laua, Martin G. Golkowskia, Shao-En Onga, and Joseph A. Beavoa,1 aDepartment of Pharmacology, University of Washington, Seattle, WA 98195 Contributed by Joseph A. Beavo, May 28, 2017 (sent for review March 10, 2017; reviewed by Paul M. Epstein, Donald H. Maurice, and Kjetil Tasken) Specific functions for different cyclic nucleotide phosphodiester- to bias T-helper polarization toward Th2, Treg, or Th17 pheno- ases (PDEs) have not yet been identified in most cell types. types (13, 14). In a few cases increased cAMP may even potentiate Conventional approaches to study PDE function typically rely on the T-cell activation signal (15), particularly at early stages of measurements of global cAMP, general increases in cAMP- activation. Recent MS-based proteomic studies have been useful dependent protein kinase (PKA), or the activity of exchange in characterizing changes in the phosphoproteome of T cells under protein activated by cAMP (EPAC). Although newer approaches various stimuli such as T-cell receptor stimulation (16), prosta- using subcellularly targeted FRET reporter sensors have helped glandin signaling (17), and oxidative stress (18), so much of the define more compartmentalized regulation of cAMP, PKA, and total Jurkat phosphoproteome is known. Until now, however, no EPAC, they have limited ability to link this regulation to down- information on the regulation of phosphopeptides by PDEs has stream effector molecules and biological functions. To address this been available in these cells. problem, we have begun to use an unbiased mass spectrometry- Inhibitors of cAMP PDEs are useful tools to study PKA/EPAC- based approach coupled with treatment using PDE isozyme- mediated signaling, and selective inhibitors for each of the 11 PDE – selective inhibitors to characterize the phosphoproteomes of the families have been developed (19 21). -
Human Erythrocyte Acetylcholinesterase in Health and Disease
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Universidade de Lisboa: Repositório.UL molecules Review Human Erythrocyte Acetylcholinesterase in Health and Disease Carlota Saldanha Instituto de Bioquímica, Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Av. Professor Egas Moniz, 1649-028 Lisboa, Portugal; [email protected] Received: 10 August 2017; Accepted: 4 September 2017; Published: 8 September 2017 Abstract: The biochemical properties of erythrocyte or human red blood cell (RBC) membrane acetylcholinesterase (AChE) and its applications on laboratory class and on research are reviewed. Evidence of the biochemical and the pathophysiological properties like the association between the RBC AChE enzyme activity and the clinical and biophysical parameters implicated in several diseases are overviewed, and the achievement of RBC AChE as a biomarker and as a prognostic factor are presented. Beyond its function as an enzyme, a special focus is highlighted in this review for a new function of the RBC AChE, namely a component of the signal transduction pathway of nitric oxide. Keywords: acetylcholinesterase; red blood cells; nitric oxide 1. Introduction Erythrocytes or red blood cells (RBC) are more than sacks of oxyhemoglobin or deoxyhemoglobin during the semi-life of 120 days in blood circulation [1]. Erythrocytes comport different signaling pathways which includes the final stage of apoptosis, also called eryptosis [2,3]. Exovesicules enriched with acetylcholinesterase (AChE) originated from membranes of aged erythrocytes appear in plasma [4]. Kinetic changes of the AChE enzyme have been observed in old erythrocytes [5]. Previously, AChE in erythrocytes was evidenced as a biomarker of membrane integrity [6]. -
Drug Name Plate Number Well Location % Inhibition, Screen Axitinib 1 1 20 Gefitinib (ZD1839) 1 2 70 Sorafenib Tosylate 1 3 21 Cr
Drug Name Plate Number Well Location % Inhibition, Screen Axitinib 1 1 20 Gefitinib (ZD1839) 1 2 70 Sorafenib Tosylate 1 3 21 Crizotinib (PF-02341066) 1 4 55 Docetaxel 1 5 98 Anastrozole 1 6 25 Cladribine 1 7 23 Methotrexate 1 8 -187 Letrozole 1 9 65 Entecavir Hydrate 1 10 48 Roxadustat (FG-4592) 1 11 19 Imatinib Mesylate (STI571) 1 12 0 Sunitinib Malate 1 13 34 Vismodegib (GDC-0449) 1 14 64 Paclitaxel 1 15 89 Aprepitant 1 16 94 Decitabine 1 17 -79 Bendamustine HCl 1 18 19 Temozolomide 1 19 -111 Nepafenac 1 20 24 Nintedanib (BIBF 1120) 1 21 -43 Lapatinib (GW-572016) Ditosylate 1 22 88 Temsirolimus (CCI-779, NSC 683864) 1 23 96 Belinostat (PXD101) 1 24 46 Capecitabine 1 25 19 Bicalutamide 1 26 83 Dutasteride 1 27 68 Epirubicin HCl 1 28 -59 Tamoxifen 1 29 30 Rufinamide 1 30 96 Afatinib (BIBW2992) 1 31 -54 Lenalidomide (CC-5013) 1 32 19 Vorinostat (SAHA, MK0683) 1 33 38 Rucaparib (AG-014699,PF-01367338) phosphate1 34 14 Lenvatinib (E7080) 1 35 80 Fulvestrant 1 36 76 Melatonin 1 37 15 Etoposide 1 38 -69 Vincristine sulfate 1 39 61 Posaconazole 1 40 97 Bortezomib (PS-341) 1 41 71 Panobinostat (LBH589) 1 42 41 Entinostat (MS-275) 1 43 26 Cabozantinib (XL184, BMS-907351) 1 44 79 Valproic acid sodium salt (Sodium valproate) 1 45 7 Raltitrexed 1 46 39 Bisoprolol fumarate 1 47 -23 Raloxifene HCl 1 48 97 Agomelatine 1 49 35 Prasugrel 1 50 -24 Bosutinib (SKI-606) 1 51 85 Nilotinib (AMN-107) 1 52 99 Enzastaurin (LY317615) 1 53 -12 Everolimus (RAD001) 1 54 94 Regorafenib (BAY 73-4506) 1 55 24 Thalidomide 1 56 40 Tivozanib (AV-951) 1 57 86 Fludarabine -
Phosphodiesterase (PDE)
Phosphodiesterase (PDE) Phosphodiesterase (PDE) is any enzyme that breaks a phosphodiester bond. Usually, people speaking of phosphodiesterase are referring to cyclic nucleotide phosphodiesterases, which have great clinical significance and are described below. However, there are many other families of phosphodiesterases, including phospholipases C and D, autotaxin, sphingomyelin phosphodiesterase, DNases, RNases, and restriction endonucleases, as well as numerous less-well-characterized small-molecule phosphodiesterases. The cyclic nucleotide phosphodiesterases comprise a group of enzymes that degrade the phosphodiester bond in the second messenger molecules cAMP and cGMP. They regulate the localization, duration, and amplitude of cyclic nucleotide signaling within subcellular domains. PDEs are therefore important regulators ofsignal transduction mediated by these second messenger molecules. www.MedChemExpress.com 1 Phosphodiesterase (PDE) Inhibitors, Activators & Modulators (+)-Medioresinol Di-O-β-D-glucopyranoside (R)-(-)-Rolipram Cat. No.: HY-N8209 ((R)-Rolipram; (-)-Rolipram) Cat. No.: HY-16900A (+)-Medioresinol Di-O-β-D-glucopyranoside is a (R)-(-)-Rolipram is the R-enantiomer of Rolipram. lignan glucoside with strong inhibitory activity Rolipram is a selective inhibitor of of 3', 5'-cyclic monophosphate (cyclic AMP) phosphodiesterases PDE4 with IC50 of 3 nM, 130 nM phosphodiesterase. and 240 nM for PDE4A, PDE4B, and PDE4D, respectively. Purity: >98% Purity: 99.91% Clinical Data: No Development Reported Clinical Data: No Development Reported Size: 1 mg, 5 mg Size: 10 mM × 1 mL, 10 mg, 50 mg (R)-DNMDP (S)-(+)-Rolipram Cat. No.: HY-122751 ((+)-Rolipram; (S)-Rolipram) Cat. No.: HY-B0392 (R)-DNMDP is a potent and selective cancer cell (S)-(+)-Rolipram ((+)-Rolipram) is a cyclic cytotoxic agent. (R)-DNMDP, the R-form of DNMDP, AMP(cAMP)-specific phosphodiesterase (PDE) binds PDE3A directly. -
Cyclic Nucleotide Phosphodiesterases in Heart and Vessels
Cyclic nucleotide phosphodiesterases in heart and vessels: A therapeutic perspective Pierre Bobin, Milia Belacel-Ouari, Ibrahim Bedioune, Liang Zhang, Jérôme Leroy, Véronique Leblais, Rodolphe Fischmeister, Grégoire Vandecasteele To cite this version: Pierre Bobin, Milia Belacel-Ouari, Ibrahim Bedioune, Liang Zhang, Jérôme Leroy, et al.. Cyclic nucleotide phosphodiesterases in heart and vessels: A therapeutic perspective. Archives of cardiovascular diseases, Elsevier/French Society of Cardiology, 2016, 109 (6-7), pp.431-443. 10.1016/j.acvd.2016.02.004. hal-02482730 HAL Id: hal-02482730 https://hal.archives-ouvertes.fr/hal-02482730 Submitted on 23 Mar 2020 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Cyclic nucleotide phosphodiesterases in heart and vessels: A therapeutic perspective Abbreviated title: Cyclic nucleotide phosphodiesterases in heart and vessels French title: Phosphodiestérases des nucléotides cycliques dans le cœur et les vaisseaux : une perspective thérapeutique. Pierre Bobin, Milia Belacel-Ouari, Ibrahim Bedioune, Liang Zhang, Jérôme Leroy, Véronique Leblais, Rodolphe Fischmeister*, Grégoire Vandecasteele* UMR-S 1180, INSERM, Université Paris-Sud, Université Paris-Saclay, Châtenay-Malabry, France * Corresponding authors. UMR-S1180, Faculté de Pharmacie, Université Paris-Sud, 5 rue J.-B. Clément, F-92296 Châtenay-Malabry Cedex, France. -
Anagrelide for Gastrointestinal Stromal Tumor
Author Manuscript Published OnlineFirst on December 7, 2018; DOI: 10.1158/1078-0432.CCR-18-0815 Author manuscripts have been peer reviewed and accepted for publication but have not yet been edited. 1 Anagrelide for gastrointestinal stromal tumor Olli-Pekka Pulkka1, Yemarshet K. Gebreyohannes2, Agnieszka Wozniak2, John-Patrick Mpindi3, Olli Tynninen4, Katherine Icay5, Alejandra Cervera5, Salla Keskitalo6, Astrid Murumägi3, Evgeny Kulesskiy3, Maria Laaksonen7, Krister Wennerberg3, Markku Varjosalo6, Pirjo Laakkonen8, Rainer Lehtonen5, Sampsa Hautaniemi5, Olli Kallioniemi3, Patrick Schöffski2, Harri Sihto1*, and Heikki Joensuu1,9* 1Laboratory of Molecular Oncology, Research Programs Unit, Translational Cancer Biology, Department of Oncology, University of Helsinki, Helsinki, Finland. 2Laboratory of Experimental Oncology, Department of Oncology, KU Leuven and Department of General Medical Oncology, University Hospitals Leuven, Leuven, Belgium. 3Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Helsinki, Finland 4Department of Pathology, Haartman Institute, University of Helsinki and HUSLAB, Helsinki, Finland. 5Research Programs Unit, Genome-Scale Biology, Medicum and Department of Biochemistry and Developmental Biology, Faculty of Medicine, University of Helsinki, Helsinki, Finland. 6Institute of Biotechnology, University of Helsinki, Helsinki, Finland. 7MediSapiens Ltd., Helsinki, Finland 8Research Programs Unit, Translational Cancer Biology, University of Helsinki, Helsinki, Finland. 9Comprehensive Cancer Center, -
Interaction of Phosphodiesterase 3A with Brefeldin A-Inhibited Guanine Nucleotide-Exchange Proteins BIG1 and BIG2 and Effect on ARF1 Activity
Interaction of phosphodiesterase 3A with brefeldin A-inhibited guanine nucleotide-exchange proteins BIG1 and BIG2 and effect on ARF1 activity Ermanno Puxeddu, Marina Uhart, Chun-Chun Li, Faiyaz Ahmad, Gustavo Pacheco-Rodriguez, Vincent C. Manganiello, Joel Moss, and Martha Vaughan1 Translational Medicine Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892 Contributed by Martha Vaughan, February 11, 2009 (sent for review September 22, 2008) ADP-ribosylation factors (ARFs) have crucial roles in vesicular (11). Two-hybrid interaction of the BIG2 N-terminal region with trafficking. Brefeldin A-inhibited guanine nucleotide-exchange exocyst subunit Exo70 was confirmed by coimmunoprecipitation proteins (BIG)1 and BIG2 catalyze the activation of class I ARFs by (co-IP) of the in vitro-translated proteins; microscopically, the accelerating replacement of bound GDP with GTP. Several addi- endogenous proteins appeared together along microtubules tional and differing actions of BIG1 and BIG2 have been described. (12);3Akinase-anchoring protein (AKAP) sequences in the These include the presence in BIG2 of 3 A kinase-anchoring protein N-terminal region of BIG2, one of which is identical in BIG1, (AKAP) domains, one of which is identical in BIG1. Proteins that were identified in yeast 2-hybrid experiments with 4 different A contain AKAP sequences act as scaffolds for the assembly of PKA kinase R subunits and multiple peptide sequences representing with other enzymes, substrates, and regulators in complexes that positions 1 to 643 of BIG2 (13). Consistent with the presence of constitute molecular machines for the reception, transduction, and AKAP sequences for each of the 4 R subunits in BIG1 and BIG2, integration of signals from cAMP or other sources, which are both proteins were coimmunoprecipitated from HepG2 cell initiated, propagated, and transmitted by chemical, electrical, or cytosol with antibodies against RI or RII, although direct mechanical means. -
Rolipram, but Not Siguazodan Or Zaprinast, Inhibits the Excitatory Noncholinergic Neurotransmission in Guinea-Pig Bronchi
Eur Respir J, 1994, 7, 306–310 Copyright ERS Journals Ltd 1994 DOI: 10.1183/09031936.94.07020306 European Respiratory Journal Printed in UK - all rights reserved ISSN 0903 - 1936 Rolipram, but not siguazodan or zaprinast, inhibits the excitatory noncholinergic neurotransmission in guinea-pig bronchi Y. Qian, V. Girard, C.A.E. Martin, M. Molimard, C. Advenier Rolipram, but not siguazodan or zaprinast, inhibits the excitatory noncholinergic neuro- Faculté de Médecine Paris-Ouest Labora- transmission in guinea-pig bronchi. Y. Qian, V. Girard C.A.E. Martin, M. Molimard, toire de Pharmacologie, Paris, France. C. Advenier. ERS Journals Ltd 1994. ABSTRACT: Theophylline has been reported to inhibit excitatory noncholinergic Correspondence: C. Advenier Faculté de Médecine Paris-Ouest but not cholinergic-neurotransmission in guinea-pig bronchi. As theophylline might Laboratoire de Pharmacologie exert this effect through an inhibition of phosphodiesterases (PDE), and since many 15, Rue de l'Ecole de Médecine types of PDE have now been described, the aim of this study was to investigate the F-75270 Paris Cedex 06 effects of three specific inhibitors of PDE on the electrical field stimulation (EFS) France of the guinea-pig isolated main bronchus in vitro. The drugs used were siguazo- dan, rolipram and zaprinast, which specifically inhibit PDE types, III, IV and V, Keywords: C-fibres respectively. neuropeptides Guinea-pig bronchi were stimulated transmurally with biphasic pulses (16 Hz, 1 phosphodiesterase inhibitors ms, 320 mA for 10 s) in the presence of indomethacin 10-6 M and propranolol 10-6 Received: March 11 1993 M. Two successive contractile responses were observed: a rapid cholinergic con- Accepted after revision August 8 1993 traction, followed by a long-lasting contraction due to a local release of neuropep- tides from C-fibre endings. -
Integrated Technologies for the Characterization Of
Integrated technologies for the characterization of phosphodiesterase (PDE) inhibitors Edmond Massuda, Lisa Fleet, Benjamin Lineberry, Laurel Provencher, Abbie Esterman, Dhanrajan Tiruchinapalli, Faith Gawthrop, Christopher Spence, Rajneesh P. Uzgare, Scott Perschke, Seth Cohen, and Hao Chen. 618.01/XX63 Caliper Life Sciences, a PerkinElmer Company, 7170 Standard Drive, Hanover, Maryland, 21076 USA Abstract Phosphodiesterases (PDEs) are a class of signal transduction enzymes regulating various cellular functions and disease Results Results progressions in a number of central or peripheral nervous system-related disorders. For example, these enzymes are involved in neurological diseases including psychosis in schizophrenia, multiple sclerosis and other neurodegenerative PDE1A PDE1B PDE2A PDE3A PDE3B PDE4A1A PDE4B1 Ki and kinact determination using 3D Fit Model 110 110 110 110 110 100 110 110 100 100 100 Percent of Maximum Activity by Time 100 conditions. Thus, safe and highly selective PDE inhibitors or modulators are becoming an important class of disease 100 90 100 90 90 90 90 90 80 90 80 80 80 80 modifying therapeutic agents. We have developed an integrated platform which includes Caliper LabChip™ microfluidic 80 70 80 70 70 70 70 70 60 70 60 60 60 60 mobility-shift assays measuring fluorescent analogs of cAMP and cGMP in conjunction with a cellular assay 60 60 50 50 50 50 50 50 50 40 40 40 40 characterizing intracellular signal transduction in cells modulated by PDE inhibitors. These technologies are useful in 40 40 40 30 30 30 30 %%