Purchase this article with an account.
Jamie Beckman, Johnnie Moore-Dotson, Erika D Eggers, Heddwen Brooks, Melissa Romero-Aleshire; Morphology of the Retina in Early Diabetes. J. Beckman, J. M. Moore-Dotson, M. J. Romero-Aleshire, H. L. Brooks and E.D. Eggers. Physiology and Biomedical Engineering, University of Arizona, Tucson, AZ. Invest. Ophthalmol. Vis. Sci. 2014;55(13):6174.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Recent studies have shown early changes in diabetic retinal activity in vivo. These deficits suggest changes in the activity or survival of retinal bipolar cells or amacrine cells. The purpose of this study is to determine if there is an early loss of retinal neurons in diabetic mice, and if a particular type of bipolar cell is targeted.
5 week old C57BL/6J and transgenic Mito-CFP mice were injected i.p. with streptozotocin (STZ, 3 injections of 75 mg/kg, n= 7 mice) or control vehicle citrate buffer (n= 7 mice). In STZ mice, diabetes was confirmed by blood glucose levels >200 mg/dL. Six weeks post injections, eyes were enucleated, retinas removed and fixed with 3% paraformaldehyde. TOPRO-3 was used in all retinas to stain nucleic acid in order to count cells in the retinal layers. Retinas from Mito-CFP mice express CFP in one type of OFF cone BC and were stained with an anti-GFP antibody. For each retina, four sections (143 μm2) 500 μm from the optic nerve head in each direction were imaged with a confocal microscope. The cell numbers from each section were averaged for each retina. Stained cells were counted in ImageJ and statistics were done using the Student’s T-test.
The average cells/area in the ganglion cell layer were not different between control (10563 + 411 cells/mm2, n=7) and STZ (10571 + 840 cells/mm2, n=7, p= .99) mice. There was no significant difference in cell numbers of in the inner nuclear layer for control (38169 + 1642 cells/mm2, n=7) versus the STZ (34592 + 891 cells/mm2, n=7, p= .08). There was also no significant difference in cell numbers in the outer nuclear layer of control (56695 + 784 cells/mm2, n=7) versus STZ (56524 + 747 cells/mm2, n=7, p= .87). OFF bipolar cell staining from Mito-CFP retinas show no significant differences cell number in control (3657 + 218 cells/mm2, n=3) versus STZ (3848 + 469 cells/mm2, n=3, p= .73).
These results suggest that there is no significant loss of retinal cells after a short duration of diabetes. At this same early stage of diabetes significant changes in in vivo (ex. Aung et al, 2013) and in vitro (ARVO abstract Moore-Dotson et al, 2013) retinal activity have been reported. This indicates that there are changes in neural circuits before there is any significant cell loss.
This PDF is available to Subscribers Only