CEFYBO   02669
CENTRO DE ESTUDIOS FARMACOLOGICOS Y BOTANICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
EFFECT OF EXPERIMENTAL DIABETIC RETINOPATHY ON THE NON-IMAGE FORMING VISUAL SYSTEM
Autor/es:
SANDE PABLO; DE ZAVALÍA, NURIA; BELFORTE, NICOLAS; DORFMAN D; ROSENSTEIN, RUTH; DIEGO FERNANDEZ
Lugar:
Seattle
Reunión:
Congreso; The Association For Research In Vision And Ophthalmology (Arvo); 2013
Institución organizadora:
ARVO
Resumen:
Abstract
Purpose:We investigated the non-image
forming visual system in an advanced stage of experimental diabetes in rats.
Methods: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.
Results: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.
Conclusions: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.