advertisement
Abstract #8060 Published in IGR 4-3
Endothelin-A receptor antagonist BQ-485 protects against intraocular pressure spike induced by laser trabeculoplasty in the rabbit
Holló G; Kóthy P; Lakatos P; Vargha POphthalmologica 2002; 216: 459-462
PURPOSE: The authors have previously shown in rabbits that the intraocular pressure (IOP) spike caused by argon laser trabeculoplasty (ALT) is associated with an acute endothelin-1 (ET-1) release from the uveal tissue into the aqueous humor. In this study, they investigated whether pretreatment with an ETA receptor antagonist (BQ-485) protects against the pressure spike induced by ALT, in the rabbit model. METHODS: Under general anesthesia, 10 μl of 10-5M BQ-485 was injected into the anterior chamber of the right eye, and 10 μl of balanced salt solution (BSS) into the contralateral anterior chamber, for 12 pigmented rabbits. Five minutes later ALT (1000 mW, 0.1 sec, 100 spots over 360° focused on the iris pillars) was performed on both eyes of each animal. IOP was measured before the injections (baseline value), and also 30 minutes afterwards, using a Tono-Pen XL tonometer. Immediately after the second IOP measurement, aqueous humor was aspirated for measurement of ET-1 concentration. RESULTS: The baseline IOP (mean ± SD) was 8.08 ± 1.73 and 7.92 ± 1.78 mmHg for the right and left eyes, respectively (Duncan test, p > 0.05). At 25 minutes after ALT, the IOP of the BQ-485-pretreated right eyes remained unchanged (7.83 ± 2.44 mmHg, p > 0.05), but the IOP of the BSS-pretreated left eyes at 30 minutes increased significantly to 10.67 ± 4.70 mmHg (p < 0.05 for comparisons both with the corresponding baseline value for the same eye, and with the IOP of the contralateral eye at 30 minutes). There was no difference in aqueous humor ET-1 concentration between the corresponding right and left eyes (paired t test, p > 0.05). CONCLUSIONS: Intracameral BQ-485 pretreatment protected against the ALT-induced acute IOP elevation, but did not influence the laser-induced ET-1 release. This suggests that ETA receptor antagonists may potentially have a therapeutic role in the prevention of laser-induced IOP spikes.
G. Holló, MD, PhD, 1st Department of Ophthalmology, Semmelweis University, H-1083 Budapest, Tomo u. 25-29. Hungary. hg@szem1.sote.hu
Classification:
11.14 Investigational drugs; pharmacological experiments (Part of: 11 Medical treatment)
