PURPOSE: To determine the changes in the visual centers of rats following monocular visual deprivation after postnatal eyelid opening (PEO). METHODS: Monocular eyelid suture was performed on rats on days 1, 3, 5, 7, 14, and 28 after PEO, and the glucose metabolism was measured 1, 2, 5, and 7 days after the eyelid suture. Ex vivo autoradiography with (14)C- or (18)F-labeled 2-deoxy-D-glucose was carried out. Effects of monocular enucleation or dark rearing were also determined. RESULTS: Monocular eyelid suture did not decrease the glucose metabolism in any contralateral visual structures on day 1 after visual deprivation in the PEO1 or PEO3 lid-sutured rats. However, there was a decrease on day 1 after the eyelid suture in PEO7 and older rats. Similarly, monocular enucleation on PEO1 did not reduce the glucose metabolism in the visual cortex (VC), but enucleation on PEO7 and thereafter did. Eyelid suture on PEO8 following dark rearing until PEO7 did not reduce the glucose metabolism 1 day after suture, but reduced it at 7 days after suture. CONCLUSIONS: Glucose metabolism was altered by visual deprivation on PEO7 and thereafter. Five days of visual experience after PEO were required for initiation of visual function in the rat visual system.
PURPOSE: To determine the changes in the visual centers of rats following monocular visual deprivation after postnatal eyelid opening (PEO). METHODS: Monocular eyelid suture was performed on rats on days 1, 3, 5, 7, 14, and 28 after PEO, and the glucose metabolism was measured 1, 2, 5, and 7 days after the eyelid suture. Ex vivo autoradiography with (14)C- or (18)F-labeled 2-deoxy-D-glucose was carried out. Effects of monocular enucleation or dark rearing were also determined. RESULTS: Monocular eyelid suture did not decrease the glucose metabolism in any contralateral visual structures on day 1 after visual deprivation in the PEO1 or PEO3 lid-sutured rats. However, there was a decrease on day 1 after the eyelid suture in PEO7 and older rats. Similarly, monocular enucleation on PEO1 did not reduce the glucose metabolism in the visual cortex (VC), but enucleation on PEO7 and thereafter did. Eyelid suture on PEO8 following dark rearing until PEO7 did not reduce the glucose metabolism 1 day after suture, but reduced it at 7 days after suture. CONCLUSIONS:Glucose metabolism was altered by visual deprivation on PEO7 and thereafter. Five days of visual experience after PEO were required for initiation of visual function in the rat visual system.