In Vitro Effects of Anti-Glaucomatous Eye Drops on Platelet-Activating Factor and its Metabolism.
OBJECTIVE
The purpose of this study is to determine the effect of various commonly used antiglaucoma eye drops on inflammatory mediators such as the platelet activating factor (PAF).


METHODS
Various intraocular pressure (IOP) lowering drops were tested to examine their inhibitory effect on PAF. Multiple eye drops were tested in washed rabbit platelets (WRPs) in order to determine the interaction between these eye drops and the inhibition of PAF in the PAF-induced platelet aggregation model. In addition, we examined the eyedrops' effect on PAF-metabolism, through in vitro analysis on PAF basic metabolic enzymes (PAF-CPT, lyso PAF-AT, and PAF-AH).


RESULTS
Latanoprost (Xalatan) was found to be the most potent in inhibiting PAF, suggesting that it is the most effective in decreasing IOP amongst the eye drops tested. Conversely, dorzolamide hydrochloride-timolol (Cosopt) exhibited the least anti-PAF action.


CONCLUSIONS
This is the first study examine the relationship between PAF activity and glaucoma medication. Potency in PAF inhibition may be related to drop efficacy.
a Laboratory of Electrophysiology, 1st Department of Ophthalmology , University of Athens , Athens , Greece.
Marilita M
MM
Moschos
a Laboratory of Electrophysiology, 1st Department of Ophthalmology , University of Athens , Athens , Greece.
Irini P
IP
Chatziralli
b Laboratory of Biochemistry, Faculty of Chemistry , University of Athens , Athens , Greece , and.
George
G
Stamatakis
b Laboratory of Biochemistry, Faculty of Chemistry , University of Athens , Athens , Greece , and.
Vasiliki D
VD
Papakonstantinou
c Cambridge University Hospitals NHS Foundation Trust , Cambridge , UK.
Michael
M
Tsatsos
b Laboratory of Biochemistry, Faculty of Chemistry , University of Athens , Athens , Greece , and.
Constantinos A
CA
Demopoulos
D000818:Animals; D004195:Disease Models, Animal; D004338:Drug Combinations; D005901:Glaucoma / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D007429:Intraocular Pressure / Q000502:physiology*; D009883:Ophthalmic Solutions / Q000008:administration & dosage; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors* / Q000378:metabolism; D010974:Platelet Aggregation / Q000187:drug effects; D011817:Rabbits; D013449:Sulfonamides / Q000008:administration & dosage*; D013876:Thiophenes / Q000008:administration & dosage*; D013999:Timolol / Q000008:administration & dosage*
D004338:Drug Combinations; D009883:Ophthalmic Solutions; D010972:Platelet Activating Factor; D013449:Sulfonamides; D013876:Thiophenes; C479140:dorzolamide-timolol combination; D013999:Timolol
Eye drops; PAF; glaucoma; metabolism