Contribution focused to clarify correlation between mixtures of the free amino acids with antiglaucomatics in influencing the IOP in rabbits after application into the conjunctival sac
Oláh, Z.; Veselovský, J.
Ceska a Slovenska Oftalmologie Casopis Ceske Oftalmologicke Spolecnosti a Slovenske Oftalmologicke Spolecnosti 69(1): 41-44
2013
ISSN/ISBN: 1211-9059 PMID: 23822601 Document Number: 667074
Correlation between the amino acid L-arginine.HCl and 3 antiglaucomatics (Timolol, Xalatan or Trusopt) mixture in their effect on the physiological IOP values in rabbits Methods: The experimental works were performed on 5 female rabbits of the New Zealand White species. After instillation of the 2 drops of in vitro prepared 10% solution of the amino acid L-arginine.HCl in 0.5% Timolol maleat (Timoptol, Zentiva), 0.005% Lanatosid (Xalatan, Pharmacia&Upjohn) or 2% Trusopt (Dorsolamid, Merc&Co.) at 8, 00 am. into the left conjunctival sac the IOP was measured before and in 15th, 30th, 60th, 120th, 180th, 240th min. and 24 hours after instillation. The right eye was used as control. The amino acid 10% L-arginine.HCl solution applicated separately decreased the physiologic IOP in rabbits in confrontation with the control eyes for - 2.9 torr. The antiglaucomatics applicated separately reduced the IOP values for: 0.5% Timoptol -0,69 torr, 0.005% Xalatan -2.1 torr and 2% Trusopt -2.45 torr . The 10% L-arginine.HCl in combination with the antiglaucomatics decreased the physiologic IOP by these values: in mixture with 0.5% Timolol by -3.32 torr (16.3% compared with control, but 4.8 times lower in confrontation with 0,5% Timolol); with 0.005% Xalatan by -2.91 torr (exactly the same decrease as measured after the 0.005% Xalatan separate application); with 2% Trusopt by - 4.45 torr (23.8% compared with control, but only 1.99 times lower compared with 2% Trusopt). In our experiments we applicated into the conjunctival sac in fact the already ready in vitro prepared metabolite ("bio antiglaucomatic") that can immediately penetrate the hemato-ocular barrier and enter into the target area. These experiments proved different relation between the amino acid L-arginine HCL and various antiglaucomatics. The 10% L-arginine HCL mixture with 0.5% Timoptol decreased the IOP values for more than 5x compared with Timoptol alone and mixture of the same substance with 2% Trusopt showed almost two-fold decrease (-1.99 torr, also compared with Timoptol). Comparing the L-arginine HCL mixture with 0.005% Xalatan with Xalatan alone no increased effectivity was constated. These differences in results are proving the individual specificity in influencing the IOP in rabbits by interaction of the specific amino acid in mixture with antiglaucomatics applicated into the conjunctival sac.