title: Vasoactive responses of U46619, PGF2alpha, latanoprost, and travoprost in isolated porcine ciliary arteries.
abstract: OBJECTIVE
  To compare the vasoactive properties of the prostanoids U46619 (thromboxane A2 analogue), prostaglandin F(2alpha) (PGF(2alpha)), latanoprost free acid, and travoprost free acid in isolated porcine ciliary arteries.
  
  
  METHODS
  In a myograph system (isometric force measurement), quiescent vessels were exposed (cumulatively) to U46619, PGF(2alpha), latanoprost, or travoprost (0.1 nM-0.1 mM). Experiments were also conducted in the presence of SQ 29548 (TP-receptor antagonist; 3-10 microM) or AL-8810 (FP-receptor antagonist; 3-30 microM). Contractions were expressed as the percentage of 100 mM potassium chloride-induced contractions.
  
  
  RESULTS
  In quiescent vessels, contractions (concentration-response curves) induced by (0.1 mM) PGF(2alpha) (87.9% +/- 3.5%), U46619 (66.7% +/- 4.1%), and latanoprost (62.9% +/- 3.6%) were more pronounced (P < or = 0.001) than those induced by travoprost (23.0% +/- 4.4%). Concentration-response curves for PGF(2alpha), latanoprost, and travoprost were preceded by a smaller contraction peak (0.1 microM) that was higher (P < or = 0.05) for travoprost (24.4% +/- 2.8%) than for PGF(2alpha) (12.9% +/- 4.6%), but not different (P = 0.58) from latanoprost (22.0% +/- 3.0%). The 50% maximal contraction (PD50: negative log M concentration) of U46619 (-8.05 +/- 0.13) was lower (P < or = 0.001) than those of latanoprost (-5.65 +/- 0.10), PGF(2alpha) (-5.49 +/- 0.14), and travoprost (-5.12 +/- 0.52). Contractions were inhibited (P < or = 0.05-0.001) either by SQ 29548 or AL-8810.
  
  
  CONCLUSIONS
  In isolated porcine ciliary arteries, all prostanoids tested induced contractions. Among them, travoprost appeared to be the least potent and U46619 the most efficient.
authors.affiliation: Laboratory of Pharmacology and Physiology, University Eye Clinic, Basel, Switzerland.
authors.forename: Ineta
authors.initials: I
authors.lastname: Vysniauskiene
authors.forename: Reto
authors.initials: R
authors.lastname: Allemann
authors.forename: Josef
authors.initials: J
authors.lastname: Flammer
authors.forename: Ivan O
authors.initials: IO
authors.lastname: Haefliger
mesh_terms: D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid / Q000494:pharmacology*; D000818:Animals; D019086:Bridged Bicyclo Compounds, Heterocyclic; D019842:Ciliary Arteries / Q000187:drug effects* / Q000502:physiology; D003008:Cloprostenol / Q000031:analogs & derivatives* / Q000494:pharmacology; D015237:Dinoprost / Q000031:analogs & derivatives / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005231:Fatty Acids, Unsaturated; D006834:Hydrazines / Q000494:pharmacology; D000077338:Latanoprost; D011461:Prostaglandins F, Synthetic / Q000494:pharmacology*; D011982:Receptors, Prostaglandin / Q000037:antagonists & inhibitors; D017482:Receptors, Thromboxane / Q000037:antagonists & inhibitors; D013552:Swine; D000069557:Travoprost; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology; D014662:Vasoconstrictor Agents / Q000494:pharmacology*
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D005231:Fatty Acids, Unsaturated; D006834:Hydrazines; D011461:Prostaglandins F, Synthetic; D011982:Receptors, Prostaglandin; D017482:Receptors, Thromboxane; D014662:Vasoconstrictor Agents; C121227:AL 8810; D003008:Cloprostenol; D000077338:Latanoprost; D019796:15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid; C045749:SQ 29548; D015237:Dinoprost; D000069557:Travoprost