Purchase this article with an account.
Pablo Sande, Nuria de Zavalia, Nicolas Belforte, Damian Dorfman, Ruth Rosenstein, Diego Fernandez; EFFECT OF EXPERIMENTAL DIABETIC RETINOPATHY ON THE NON-IMAGE FORMING VISUAL SYSTEM. Invest. Ophthalmol. Vis. Sci. 2013;54(15):2695.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
We investigated the non-image forming visual system in an advanced stage of experimental diabetes in rats.
Male Wistar rats were injected (i.p.) with vehicle or streptozotocin. A group of animals was submitted to bilateral lensectomy. Retinal (ERG), and visual pathway (visual evoked potentials) function, the number of Brn3a(+) and melanopsin(+) RGC (immunohistochemistry), and melanopsin levels (Western Blot) were examined. The pupil light reflex (PRL) (after 30-s light flash), and light-induced c-Fos expression in the suprachiasmatic nuclei (SCN) were assessed. Anterograde transport was examined after an intravitreal injection of cholera toxin β-subunit, and circadian rhythms of general locomotor activity were registered in cages equipped with infrared detectors of motion.
After 15 weeks of diabetes induction, clear alterations in the visual function were observed. Concomitantly with a significant decrease in the number of Brn3a(+) RGC, no differences in the number of melanopsin(+) cells, melanopsin levels, and retinal projections to the SCN and the olivary pretectal nucleus were observed. However, a significant decrease in light induced c-Fos expression in the SCN was found. In diabetic animals, the afferent PLR and the locomotor activity pattern appear to be conserved, although a delay in the time needed to re-entrainment after a phase delay was observed. In diabetic animals, lensectomy reversed the alterations in c-Fos expression and in the locomotor activity rhythm.
These results indicate that the neuronal substrate of the non-image forming visual system remained largely unaffected at advanced stages of diabetes and lensectomy, a relatively easy and safe surgery, could restore circadian alterations induced by diabetes.
This PDF is available to Subscribers Only