A Randomized, Controlled Comparison of NCX 470 (0.021%, 0.042%, and 0.065%) and Latanoprost 0.005% in Patients With Open-angle Glaucoma or Ocular Hypertension: The Dolomites Study.

Prcis: NCX 470 0.042% and 0.065% were statistically superior in intraocular pressure (IOP) lowering to latanoprost 0.

Glycine reduces platelet aggregation.

It has been demonstrated that a wide variety of white blood cells and macrophages (i.e. Kupffer cells, alveolar and peritoneal macrophages and neutrophils) contain glycine-gated chloride channels.

P2Y₂ receptor activation decreases blood pressure and increases renal Na⁺ excretion.

ATP and UTP are endogenous agonists of P2Y(2/4) receptors. To define the in vivo effects of P2Y(2) receptor activation on blood pressure and urinary excretion, we compared the response to INS45973, a P2Y(2/4) receptor agonist and UTP analog, in wild-type (WT) and P2Y(2) receptor knockout (P2Y(2)-/-) mice. INS45973 was administered intravenously as a bolus injection or continuous infusion to determine effects on blood pressure and renal function, respectively.

Transformation by a nucleotide-activated P2Y receptor is mediated by activation of Galphai, Galphaq and Rho-dependent signaling pathways.

Background: Nucleotide-actived P2Y receptors play critical roles in the growth of tumor cells by regulating cellular proliferation, differentiation and survival.

Results: Here we demonstrate that an avian P2Y purinoceptor (tP2YR) with unique pharmacological and signal transduction properties induces morphologic and growth transformation of rodent fibroblasts. tP2YR induced a transformed phenotype similar to the mas oncogene, a G protein-coupled receptor which causes transformation by activation of Rac-dependent pathways.

Ocular surface distribution and pharmacokinetics of a novel ophthalmic 1% azithromycin formulation.

Purpose: To investigate the ocular distribution of 1% azithromycin ophthalmic solution and the effect of polycarbophil-based mucoadhesive formulation on ocular tissue levels of azithromycin after single and multiple topical administrations in the rabbit eye.

Methods: Rabbits were treated with either a single administration of 1% azithromycin solution with or without polycarbophil, or with multiple administrations of 1% azithromycin solution in polycarbophil. Drug concentrations were measured using LC/MS/MS.

Structure-activity relationships of dinucleotides: Potent and selective agonists of P2Y receptors.

Dinucleoside polyphosphates act as agonists on purinergic P2Y receptors to mediate a variety of cellular processes. Symmetrical, naturally occurring purine dinucleotides are found in most living cells and their actions are generally known. Unsymmetrical purine dinucleotides and all pyrimidine containing dinucleotides, however, are not as common and therefore their actions are not well understood.

Adenosine analogues as inhibitors of P2Y12 receptor mediated platelet aggregation.

Modified adenosine derivatives may lead to the development of P2Y(12) antagonists that are potent, selective, and bind reversibly to the receptor. Analogues of 2',3'-trans-styryl acetal-N6-ureido-adenosine monophosphate were prepared by modification of the 5'-position. The resulting analogues were tested for P2Y(12) antagonism in a platelet aggregation assay.

Lipophilic modifications to dinucleoside polyphosphates and nucleotides that confer antagonist properties at the platelet P2Y12 receptor.

Platelet P2Y12 receptors play a central role in the regulation of platelet function and inhibition of this receptor by treatment with drugs such as clopidogrel results in a reduction of atherothrombotic events. We discovered that modification of natural and synthetic dinucleoside polyphosphates and nucleotides with lipophilic substituents on the ribose and base conferred P2Y12 receptor antagonist properties to these molecules producing potent inhibitors of ADP-mediated platelet aggregation. We describe methods for the preparation of these functionalized dinucleoside polyphosphates and nucleotides and report their associated activities.

Nucleotide P2Y1 receptor regulates EGF receptor mitogenic signaling and expression in epithelial cells.

Epidermal growth factor receptor (EGFR) function is transregulated by a variety of stimuli, including agonists of certain G-protein-coupled receptors (GPCRs). One of the most ubiquitous GPCRs is the P2Y(1) receptor (P2RY1, hereafter referred to as P2Y(1)R) for extracellular nucleotides, mainly ADP. Here, we show in tumoral HeLa cells and normal FRT epithelial cells that P2Y(1)R broadcasts mitogenic signals by transactivating the EGFR.

Paralytic ileus: a complication after intrathecal baclofen therapy.

Introduction: Baclofen is frequently used in the management of spasticity. When the therapeutic benefit of oral baclofen is not satisfactory, intrathecal administration should be considered. This method reduces side effects due to a reduction in dosage compared to oral administration.

International Union of Pharmacology LVIII: update on the P2Y G protein-coupled nucleotide receptors: from molecular mechanisms and pathophysiology to therapy.

There have been many advances in our knowledge about different aspects of P2Y receptor signaling since the last review published by our International Union of Pharmacology subcommittee. More receptor subtypes have been cloned and characterized and most orphan receptors de-orphanized, so that it is now possible to provide a basis for a future subdivision of P2Y receptor subtypes. More is known about the functional elements of the P2Y receptor molecules and the signaling pathways involved, including interactions with ion channels.

Synthesis of potential purinoceptor antagonists: application of P1-tBU phosphazene base for alkylation of adenine in solution and on solid phase.

Alkylation of adenine in solution and on solid phase was accelerated by phosphazene base P1-tBu compared to mineral bases. The reactions in solution afforded regioselectively the appropriate N9-alkylated adenines with high preparative yields while the reaction with polystyrene resin-bound N-bromoacetylated peptides gave three regioisomers (alkylated at the N9, N7, and N3 position of adenine) in a 4:2:1 molar ratio. Ten novel nonphosphate nucleotide analogues were tested in an ADP-induced platelet aggregation assay.

Regulation of P2Y1 receptor-mediated signaling by the ectonucleoside triphosphate diphosphohydrolase isozymes NTPDase1 and NTPDase2.

Ectonucleoside triphosphate diphosphohydrolases (NTPDases) control the concentration of released extracellular nucleotides, but the precise physiological roles played by these isozymes in modulation of P2 receptor signaling remain unclear. Activation of the human P2Y(1) receptor was studied in the presence of NTPDase1 or NTPDase2 expressed either in the same cell as the receptor or in P2Y(1) receptor-expressing cells cocultured with NTPDaseexpressing cells. Coexpression of NTPDase1 with the P2Y(1) receptor resulted in increases in the EC(50) for 2'-methylthioadenosine 5'-diphosphate (2MeSADP; 12-fold), ADP (50-fold), and ATP (10-fold) for activation of phospholipase C.

Induction of novel agonist selectivity for the ADP-activated P2Y1 receptor versus the ADP-activated P2Y12 and P2Y13 receptors by conformational constraint of an ADP analog.

ADP is the cognate agonist of the P2Y1, P2Y12, and P2Y13 receptors. With the goal of identifying a high potency agonist that selectively activates the P2Y1 receptor, we examined the pharmacological selectivity of the conformationally constrained non-nucleotide analog (N)-methanocarba-2MeSADP [(1'S,2'R, 3'S,4'R,5'S)-4-[(6-amino-2-methylthio-9H-purin-9-yl)-1-diphosphoryloxymethyl]bicyclo[3.1.

Purification and functional reconstitution of the human P2Y12 receptor.

The human P2Y12 receptor (P2Y12-R) is a member of the G protein coupled P2Y receptor family, which is intimately involved in platelet physiology. We describe here the purification and functional characterization of recombinant P2Y12-R after high-level expression from a baculovirus in Sf9 insect cells. Purified P2Y12-R, Gbeta1gamma2, and various Galpha-subunits were reconstituted in lipid vesicles, and steady-state GTPase activity was quantified.

Requirement of Cys399 for processing of the human ecto-ATPase (NTPDase2) and its implications for determination of the activities of splice variants of the enzyme.

Ecto-ATPase (CD39L1) corresponds to the type 2 enzyme of the ecto-nucleoside triphosphate diphosphohydrolase family (E-NTPDase). We have isolated from human ECV304 cells three cDNAs with high homology with members of the E-NTPDase family that encode predicted proteins of 495, 472, and 450 amino acids. Sequencing of a genomic DNA clone confirmed that these three sequences correspond to splice variants of the human ecto-ATPase (NTPDase2 alpha,-2 beta, and -2 gamma).

The hypolipidemic drug metabolites nafenopin-CoA and ciprofibroyl-CoA are competitive P2Y1 receptor antagonists.

Coenzyme A (CoA-SH), endogenous and drug-derived CoA-derivatives were tested as putative antagonists of P2Y receptors expressed in Xenopus laevis oocytes, a method used to determine calcium-activated chloride current, an indicator of the activation of these receptors. CoA-SH antagonized reversibly and in a concentration-dependent manner the ATP-gated currents evoked by the human P2Y(1) but not the P2Y(2) receptor. Palmitoyl-CoA was four-fold more potent than CoA-SH as an antagonist while palmitoyl-carnitine was inactive, highlighting the role of the CoA-SH moiety in the antagonism.

Characterization of the UDP-glucose receptor (re-named here the P2Y14 receptor) adds diversity to the P2Y receptor family.

The cloning of a human G-protein-coupled receptor (GPCR) that specifically responds to UDP-glucose and related sugar-nucleotides has been reported recently. This receptor has important structural similarities to known members of the P2Y receptor family but also shows a distinctly different pharmacological response profile. Here, the IUPHAR Subcommittee for P2Y receptor nomenclature and classification review the current knowledge of this receptor and present their reasons for including this receptor in the P2Y receptor family as the P2Y(14) receptor.

Quantitation of the P2Y(1) receptor with a high affinity radiolabeled antagonist.

2-Chloro-N(6)-methyl-(N )-methanocarba-2'-deoxyadenosine-3',5'- bisphosphate (MRS2279) was developed previously as a selective high-affinity, non-nucleotide P2Y(1) receptor (P2Y1-R) antagonist (J Med Chem 43:829-842, 2002; Br J Pharmacol 135:2004-2010, 2002). We have taken advantage of the N(6)-methyl substitution in the adenine base to incorporate [(3)H]methylamine into the synthesis of [(3)H]MRS2279 to high (89 Ci/mmol) specific radioactivity and have used this molecule as a radioligand for the P2Y1-R. [(3)H]MRS2279 bound to membranes from Sf9 insect cells expressing recombinant human P2Y1-R but not to membranes from wild-type Sf9 cells or Sf9 cells expressing high levels of recombinant P2Y(2) or P2Y(12) receptors.

A fusion protein of the human P2Y(1) receptor and NTPDase1 exhibits functional activities of the native receptor and ectoenzyme and reduced signaling responses to endogenously released nucleotides.

To begin to address the functional interactions between constitutively released nucleotides, ectonucleotidase activity, and P2Y receptor-promoted signaling responses, we engineered the human P2Y(1) receptor in a fusion protein with a member of the ectonucleoside triphosphate diphosphohydrolase family, NTPDase1. Membranes prepared from Chinese hamster ovary (CHO)-K1 cells stably expressing either wild-type NTPDase1 or the P2Y(1) receptor-NTPDase1 fusion protein exhibited nucleotide-hydrolytic activities that were over 300-fold greater than activity measured in membranes from empty vector-transfected cells. The molecular ratio for nucleoside triphosphate versus diphosphate hydrolysis was approximately 1:0.

Adenine nucleotide analogues locked in a Northern methanocarba conformation: enhanced stability and potency as P2Y(1) receptor agonists.

Preference for the Northern (N) ring conformation of the ribose moiety of nucleotide 5'-triphosphate agonists at P2Y(1), P2Y(2), P2Y(4), and P2Y(11) receptors, but not P2Y(6) receptors, was established using a ring-constrained methanocarba (a 3.1.0-bicyclohexane) ring as a ribose substitute (Kim et al.

2-Chloro N(6)-methyl-(N)-methanocarba-2'-deoxyadenosine-3',5'-bisphosphate is a selective high affinity P2Y(1) receptor antagonist.

1. We reported previously that bisphosphate derivatives of adenosine are antagonists of the P2Y(1) receptor and that modification of the ribose in these analogues is tolerated in the P2Y(1) receptor binding pharmacophore. 2.

Methanocarba modification of uracil and adenine nucleotides: high potency of Northern ring conformation at P2Y1, P2Y2, P2Y4, and P2Y11 but not P2Y6 receptors.

The potency of nucleotide antagonists at P2Y1 receptors was enhanced by replacing the ribose moiety with a constrained carbocyclic ring (Nandanan, et al. J. Med.