INVESTIGADORES
DORFMAN Damian
artículos
Título:
Effect of experimental diabetic retinopathy on the non-image-forming visual system
Autor/es:
FERNANDEZ DC; SANDE PH; DE ZAVALÍA N; BELFORTE NA; DORFMAN D; CASIRAGHI LP; GOLOMBEK D; ROSENSTEIN RE
Revista:
CHRONOBIOLOGY INTERNATIONAL
Editorial:
TAYLOR & FRANCIS INC
Referencias:
Lugar: Londres; Año: 2013 vol. 30 p. 583 - 597
ISSN:
0742-0528
Resumen:
Chronobiol Int. 2013 May;30(4):583-97. doi: 10.3109/07420528.2012.754453. Epub 2013 Feb 27.
Effect of experimental diabetic retinopathy on the non-image-forming visual system.
Fernandez DC, Sande PH, de Zavalía N, Belforte N, Dorfman D, Casiraghi LP, Golombek D, Rosenstein RE.
Source
Laboratorio
de Neuroquímica Retiniana y Oftalmología Experimental, Departamento de
Bioquímica Humana, Facultad de Medicina/CEFyBO, Universidad de Buenos
Aires/CONICET, Buenos Aires, Argentina.
Abstract
Diabetic
retinopathy is a leading cause of blindness. Intrinsically
photosensitive retinal ganglion cells (ipRGCs), which express the
photopigment melanopsin, are involved in non-image-forming visual
responses such as photoentrainment of circadian rhythms and pupillary
light reflex. Since several reports indicate that retinal ganglion cells
are affected by diabetes, we investigated the non-image-forming visual
system in an advanced stage of experimental diabetes in rats induced by
streptozotocin. After 15 wks of diabetes induction, clear alterations in
the visual function were observed and all animals developed mature
cataracts. At this time point, concomitantly with a significant decrease
in the number of Brn3a(+) retinal ganglion cells, no differences in the
number of melanopsin-containing cells, melanopsin levels, and retinal
projections to the suprachiasmatic nuclei and the olivary pretectal
nucleus were observed. At high light intensity, afferent pupil light
reflex appears to be conserved in diabetic animals. After 15 wks of
diabetes induction, a significant decrease in light-induced c-Fos
expression in the suprachiasmatic nuclei was found. In diabetic animals,
the locomotor activity pattern was conserved, although a delay in the
time needed for 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 suggest
that the neuronal substrate of the non-image-forming visual system
remained largely unaffected at advanced stages of diabetes, and that
lensectomy, a relatively easy and safe surgery, could partially restore
circadian alterations induced by diabetes.