TY - JOUR
T1 - Carbonic anhydrase inhibition increases retinal oxygen tension and dilates retinal vessels
AU - Bach Pedersen, Daniella
AU - Koch Jensen, Peter
AU - la Cour, Morten
AU - Kiilgaard, Jens Folke
AU - Eysteinsson, Thor
AU - Bang, Kurt
AU - Wiencke, Anne Kathrine
AU - Stefánsson, Einar
N1 - Funding Information: Acknowledgements The authors thank veterinary technician Mette Olesen, veterinary nurse Letty Klarskov and other staff at the Experimental Surgery Unit, Panum Institute, University of Copenhagen for their assistance with the handling of the experimental animals. Supported by University of Copenhagen, Denmark; Merck, Sharp and Dohme, Denmark; University of Iceland Research Fund, Iceland; and Helga Jónsdóttir and Sigurlioi Kristj nsson Memorial Fund, Iceland.
PY - 2005/2
Y1 - 2005/2
N2 - Background: Carbonic anhydrase inhibitors (CAIs) increase blood flow in the brain and probably also in the optic nerve and retina. Additionally they elevate the oxygen tension in the optic nerve in the pig. We propose that they also raise the oxygen tension in the retina. We studied the oxygen tension in the pig retina and optic nerve before and after dorzolamide injection. Also the retinal vessel diameters during carbonic anhydrase inhibition were studied. Methods: A polarographic oxygen electrode was placed transvitreally immediately over the retina or the optic disc in anaesthetised pigs. The oxygen tension was recorded continually and 500 mg dorzolamide was injected intravenously. Retinal vessel diameters were analysed from monochromatic fundus photographs taken before and after injection of dorzolamide. Results: Baseline retinal oxygen tension (RPO2) was 3.34±0.50 kPa (mean ± SD, n=6) and baseline optic nerve oxygen tension (ONPO2) was 3.63±1.00 kPa. RPO2 was increased by 0.36±0.11 kPa (n=6, P=0.025) and ONPO2 by 0.73±0.34 kPa (n=6, P=0.003) 30 min after dorzolamide administration. The retinal arterioles was significantly dilated by 13±7% (n=5, P=0.016) and the retinal venules by 12±8% (n=5, P=0.030) 30 min after injection of dorzolamide. Conclusion: Retinal and optic ne rve oxygen tension increased with systemic administration of dorzolamide. The retinal vessels dilated, probably causing increased blood flow inducing the observed increase in RPO2. The increased oxygenation of retina by CAI may offer therapeutic possibilities in ischaemic diseases of the retina and optic nerve.
AB - Background: Carbonic anhydrase inhibitors (CAIs) increase blood flow in the brain and probably also in the optic nerve and retina. Additionally they elevate the oxygen tension in the optic nerve in the pig. We propose that they also raise the oxygen tension in the retina. We studied the oxygen tension in the pig retina and optic nerve before and after dorzolamide injection. Also the retinal vessel diameters during carbonic anhydrase inhibition were studied. Methods: A polarographic oxygen electrode was placed transvitreally immediately over the retina or the optic disc in anaesthetised pigs. The oxygen tension was recorded continually and 500 mg dorzolamide was injected intravenously. Retinal vessel diameters were analysed from monochromatic fundus photographs taken before and after injection of dorzolamide. Results: Baseline retinal oxygen tension (RPO2) was 3.34±0.50 kPa (mean ± SD, n=6) and baseline optic nerve oxygen tension (ONPO2) was 3.63±1.00 kPa. RPO2 was increased by 0.36±0.11 kPa (n=6, P=0.025) and ONPO2 by 0.73±0.34 kPa (n=6, P=0.003) 30 min after dorzolamide administration. The retinal arterioles was significantly dilated by 13±7% (n=5, P=0.016) and the retinal venules by 12±8% (n=5, P=0.030) 30 min after injection of dorzolamide. Conclusion: Retinal and optic ne rve oxygen tension increased with systemic administration of dorzolamide. The retinal vessels dilated, probably causing increased blood flow inducing the observed increase in RPO2. The increased oxygenation of retina by CAI may offer therapeutic possibilities in ischaemic diseases of the retina and optic nerve.
UR - https://www.scopus.com/pages/publications/14944366770
U2 - 10.1007/s00417-003-0817-3
DO - 10.1007/s00417-003-0817-3
M3 - Article
C2 - 15742212
SN - 0721-832X
VL - 243
SP - 163
EP - 168
JO - Graefe's archive for clinical and experimental ophthalmology
JF - Graefe's archive for clinical and experimental ophthalmology
IS - 2
ER -