Related Experiment Videos
Colour vision and side-effects during treatment with methazolamide
I Widengård1, A Mandahl, P Törnquist
1Department of Ophthalmology, University of Uppsala, Sweden.
Eye (London, England)
|January 1, 1995
Summary
Carbonic anhydrase (CA) inhibition in the eye may disrupt color vision, similar to Na+K(+)-ATPase inhibition. This study found CA inhibition by methazolamide impaired color discrimination in male volunteers.
Area of Science:
- Ophthalmology
- Neuroscience
- Pharmacology
Background:
- The retina possesses Na+K(+)-ATPase and carbonic anhydrase (CA), crucial enzymes for regulating photoreceptor cell membrane ion fluxes.
- Digitalis-induced inhibition of retinal Na+K(+)-ATPase is known to impair color vision.
Purpose of the Study:
- To investigate whether carbonic anhydrase (CA) inhibition also affects color vision.
- To determine if methazolamide, a CA inhibitor, causes disturbances in color discrimination.
Main Methods:
- A double-masked, placebo-controlled, cross-over study involving 14 male volunteers.
- Participants received 50 mg of methazolamide four times daily for two weeks.
- Color discrimination was assessed using the Lanthony New Color Test.
Main Results:
- Eight out of 14 subjects exhibited impaired color discrimination after methazolamide administration.
- The observed color vision disturbance was not significantly correlated with the degree of acidosis or other reported side effects.
- The findings suggest a specific effect of CA inhibition within the retina or visual cortex.
Conclusions:
- Inhibition of carbonic anhydrase (CA) in the eye can lead to disturbances in color discrimination.
- Methazolamide, a CA inhibitor, appears to specifically impact color vision pathways.
- Further research is warranted to elucidate the precise mechanism of CA inhibition's effect on visual processing.