Purpose: Glaucoma is the main cause of blindness in the developed countries. Its progress can be diminished by decreasing intraocular pressure (IOP) using pharmacological or surgical treatment. Antiglaucoma agents, alpha 2-adrenergic's receptor agonists have been known for several years as IOP lowering. Due to the fact that the majority of them turned out to be imidazoline receptor agonists, it is worth checking if selective imidazoline receptor (l1) agonists alter IOP. Preliminary animal experiments show that they lower IOP. In our study we examined the influence of rilmenidine, a potent l1 receptor agonist, on IOP in rabbits. Furthermore, we tried to find out whether l1 and alpha 2 receptor antagonists (efaroxan and rauwolscine) counteract the pharmacological effect of rilmenidine.
Material and methods: The study was conducted on adult male White New Zealand rabbits. All the substances were administered topically, and IOP was measured by applanation tonometry after topical anaesthesia before and 1, 3 and 5 hours after drug instillation.
Results: Rilmenidine showed the lowering effect on IOP at the concentration of 0.4%. Efaroxan and rauwolscine partly inhibited rilmenidine effect.
Conclusions: Rilmenidine is a potential antiglaucoma agent, though further studies are necessary.