Hypoxic stress is a risk factor of ocular neovascularization.
Hypoxia visualization may provide clues regarding the underlying cause of angiogenesis. Recently, we developed a
hypoxia-specific probe,
protein transduction domain-
oxygen-dependent degradation domain-
HaloTag-
Rhodamine (POH-
Rhodamine). In this study, we observed the localization of HIF-1α
proteins by immunohistochemistry and the fluorescence of POH-
Rhodamine on RPE-choroid flat mounts. Moreover, we compared the localization of POH-
Rhodamine with
pimonidazole which is a standard
reagent for detecting
hypoxia. Next, we investigated the effects of
triamcinolone acetonide (TAAC) against visual function that was evaluated by recording electroretinogram (ERG) and
choroidal neovascularization (CNV) development. Mice were given
laser-induced CNV using a
diode laser and treated with
intravitreal injection of TAAC. Finally, we investigated POH-
Rhodamine on CNV treated with TAAC. In this study, the fluorescence of POH-
Rhodamine and HIF-1α were co-localized in
laser-irradiated sites, and both the POH-
Rhodamine and
pimonidazole fluorescent areas were almost the same.
Intravitreal injection of TAAC restored the reduced ERG b-wave but not the a-wave and decreased the mean CNV area. Furthermore, the area of the POH-
Rhodamine-positive cells decreased. These findings indicate that POH-
Rhodamine is useful for evaluating tissue
hypoxia in a
laser-induced CNV model, suggesting that TAAC suppressed CNV through tissue
hypoxia improvement.