TY - JOUR
T1 - Retinal oxygenation and oxygen metabolism in abyssinian cats with a hereditary retinal degeneration
AU - Padnick-Silver, Lissa
AU - Kang Derwent, Jennifer J.
AU - Giuliano, Elizabeth
AU - Narfström, Kristina
AU - Linsenmeier, Robert A.
PY - 2006/8
Y1 - 2006/8
N2 - PURPOSE. To investigate the effects of a hereditary retinal degeneration on retinal oxygenation and determine whether it is responsible for the severe attenuation of retinal circulation in hereditary photoreceptor degenerations. METHODS. Seven adult Abyssinian cats affected by hereditary retinal degeneration were studied. Oxygen microelectrodes were used to collect spatial profiles of retinal oxygenation in anesthetized animals. A one-dimensional model of oxygen diffusion was fitted to the data to quantify photoreceptor oxygen utilization (QO2). RESULTS. Photoreceptor QO2 progressively decreased until it reached zero in the end stage of the disease. Average inner retinal oxygen tension remained within normal limits at all disease stages, despite the observed progressive retinal vessel attenuation. Light affected photoreceptors normally, decreasing QO2 by ∼50% at all stages of the disease. CONCLUSIONS. Loss of photoreceptor metabolism allows choroidal oxygen to reach the inner retina, attenuating the retinal circulation in this animal model of retinitis pigmentosa (RP) and probably also in human RP. As the degeneration progresses, there is a strong relationship between changes in the a-wave of the ERG and changes in rod oxidative metabolism, indicating that these two functional measures change together.
AB - PURPOSE. To investigate the effects of a hereditary retinal degeneration on retinal oxygenation and determine whether it is responsible for the severe attenuation of retinal circulation in hereditary photoreceptor degenerations. METHODS. Seven adult Abyssinian cats affected by hereditary retinal degeneration were studied. Oxygen microelectrodes were used to collect spatial profiles of retinal oxygenation in anesthetized animals. A one-dimensional model of oxygen diffusion was fitted to the data to quantify photoreceptor oxygen utilization (QO2). RESULTS. Photoreceptor QO2 progressively decreased until it reached zero in the end stage of the disease. Average inner retinal oxygen tension remained within normal limits at all disease stages, despite the observed progressive retinal vessel attenuation. Light affected photoreceptors normally, decreasing QO2 by ∼50% at all stages of the disease. CONCLUSIONS. Loss of photoreceptor metabolism allows choroidal oxygen to reach the inner retina, attenuating the retinal circulation in this animal model of retinitis pigmentosa (RP) and probably also in human RP. As the degeneration progresses, there is a strong relationship between changes in the a-wave of the ERG and changes in rod oxidative metabolism, indicating that these two functional measures change together.
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U2 - 10.1167/iovs.05-1284
DO - 10.1167/iovs.05-1284
M3 - Article
C2 - 16877443
AN - SCOPUS:33748097857
SN - 0146-0404
VL - 47
SP - 3683
EP - 3689
JO - Investigative Ophthalmology and Visual Science
JF - Investigative Ophthalmology and Visual Science
IS - 8
ER -