Purpose: In this work the effect by interaction in vitro free amino acid L-arginine.HCl and selected antiglaucomatic drugs prepared mixtures on the physiological IOP values in rabbits is compare.
Methods: The experimental works were performed on 5 female rabbits of the New Zealand White species. After instillation 2 drops of in vitro prepared 10% solution of the amino acid L-arginine.HCl with antiglacoma drugs (0.5% Timoptol, 0.005% Xalatan or 2% Trusopt) alone or in double combination mixtures 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.
Results: The amino acid 10% L-arginine.HCl solution separately decrease the physiologic IOP in rabbit’s in confrontation with control eyes -2.9 torr. After antiglaucomatics separetly the decrease of the IOP were constated -0.69 torr by 0.5% Timoptol, -2.1 torr by 0.005% Xalatan, resp. -2.45 torr by 2% Trusopt. 10% L-arginine.HCl with combination of mono antiglaucomatics mixture decrease the physiologic IOP by 0.5% Timoptol -3.32 torr, by 2% Trusopt -4.45 torr, by 0,005% Xalatan only 2.91 torr. Application of 10% L-arginine-HCl in double combination of antiglaumatics decrease the physiologic IOP by 0.5% Timoptol & 0.005% Xalatan -2.96 torr, by 2% Trusopt & 0.005% Xalatan -4,32 torr and COSOPT (fixed combination of 0.5% Timolol maleat & 2% Dorsolamide.HCl) only -1.8 torr.
Conclusions: We assume that the mentioned mixtures were able to decrease the physiologic IOP in rabbits through their better penetration to the receptors of the ciliary body. The mixture of the L-arginine.HCl with antiglaucomaticum Timoptol or Trusopt, resp. double combination of Timoptol & Xalatan or Trusopt & Xalatan was twice as effective as any of the mentioned antiglaucomatic drugs used separately. We conclude that the increased effectivity of the mixtures compared with the separate components is related to the instillation of the by now ready „bioantiglaucomatic”.