title: Impact of prostaglandin glaucoma drops on platelet-activating factor action: an in vitro study.
abstract: OBJECTIVE
  The aim of this study was to investigate the effect of different prostaglandin analogs on platelet-activating factor (PAF) levels.
  
  
  METHODS
  Three prostaglandin analogs were selected: bimatoprost 0.3 mg/mL, latanoprost 50 μg/mL, and tafluprost 15 μg/mL. Each drug sample was tested for its ability to cause platelet aggregation, which was measured as PAF-induced aggregation, before and after the addition of various concentrations of the examined sample, creating a linear curve of percentage inhibition (ranging from 0% to 100%) versus different concentrations of the sample. The concentration of the sample that inhibited 50% PAF-induced aggregation was calculated based on this curve, and this value was defined as IC50. In addition, the effect of eye drops on PAF metabolism was examined, through an in vitro analysis on PAF basic metabolic enzymes (PAF-cholinephosphotransferase, PAF-acetyl-CoA:1-O-alkyl-sn-glycero-3-phosphocholine acetyltransferase, and PAF-acetylhydrolase).
  
  
  RESULTS
  The IC50 values for Lumigan UD®(bimatoprost 0.3 mg/mL), Monoprost®(latanoprost 50 μg/mL), and Saflutan (tafluprost 15 μg/mL) were 8.7, 0.28, and 1.4 μg/mL, respectively.
  
  
  CONCLUSIONS
  All three prostaglandin analogs suspended PAF, but bimatoprost induced the most potent inhibition, compared to tafluprost and to the weak effect of latanoprost.
authors.affiliation: 1st Department of Ophthalmology, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
authors.forename: Marilita M
authors.initials: MM
authors.lastname: Moschos
authors.affiliation: 1st Department of Ophthalmology, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
authors.forename: Eirini
authors.initials: E
authors.lastname: Nitoda
authors.affiliation: 1st Department of Ophthalmology, Medical School, National and Kapodistrian University of Athens, Athens, Greece.
authors.forename: Irini P
authors.initials: IP
authors.lastname: Chatziralli
authors.affiliation: Department of Ophthalmology, Geneva University Hospitals (HUG), University of Geneva, Geneva, Switzerland.
authors.forename: Georgios D
authors.initials: GD
authors.lastname: Panos
authors.affiliation: Laboratory of Biochemistry, National and Kapodistrian University of Athens, Athens, Greece.
authors.forename: Constantinos A
authors.initials: CA
authors.lastname: Demopoulos
mesh_terms: D060433:Administration, Ophthalmic; D000069580:Bimatoprost / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D001792:Blood Platelets / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004339:Drug Compounding; D005901:Glaucoma / Q000188:drug therapy*; D006801:Humans; D000077338:Latanoprost; D009883:Ophthalmic Solutions; D010972:Platelet Activating Factor / Q000378:metabolism*; D010974:Platelet Aggregation / Q000187:drug effects*; D010975:Platelet Aggregation Inhibitors / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D011460:Prostaglandins F / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*; D011461:Prostaglandins F, Synthetic / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D009883:Ophthalmic Solutions; D010972:Platelet Activating Factor; D010975:Platelet Aggregation Inhibitors; D011460:Prostaglandins F; D011461:Prostaglandins F, Synthetic; C485333:tafluprost; D000077338:Latanoprost; D000069580:Bimatoprost
keywords: glaucoma; platelet aggregation; platelet-activating factor; prostaglandin analogs; treatment