Abstract
Purpose: :
To investigate the effects of Müller cell and optic nerve astrocyte on the survival and neurite outgrowth of isolated retinal ganglion cell (RGC) from postnatal rats.
Methods: :
RGC, Muller cell, and astrocyte were isolated from three-day-old Sprague-Dawley rats, and were cultured, as reported previously. Primary culture of RGC and fifth to seventh passage of Muller cell and astrocyte were used for the experiments. As previous report, RGCs were co-cultured in serum-free medium containing 0, 5, 10, or 50 µM of S-nitroso-N-acetyl-l,l-penicillamine (SNAP) with either confluent Muller cells or confluent astrocytes that were seeded onto a semipermeable membrane for 48 hours. Then, survival rate of RGC was evaluated by flow cytometry, and the number of RGCs having neurite outgrowth and length of neurite outgrowth were evaluated by an examiner with a masked fashion about the experimental conditions.
Results: :
The survival rate of RGC was decreased by SNAP loading with a dose-dependent manner. Co-cultured both glial cells improved the survival rate, but there was no significant difference in neuroprotective effects between Müller cell and astrocyte. In contrast, astrocyte significantly increased the number of RGC having neurite by 1.5, 1.5, and 1.7 times than Müller cell at doses of 0, 5, and 10 µM of SNAP, respectively. Astrocyte also increased the length of nuerite outgrowth of RGC by 2.4, 2.9, and 1.4 times than Müller cell at doses of 0, 5, and 10 µM of SNAP, respectively. These differences between Müller cell and astrocyte were statistically significant.
Conclusions: :
Both glial cells similarly protect RGCs against nitric oxide loading, but astrocyte may be more beneficial to nurite outgrowth of RGC than Müller cell.
Keywords: ganglion cells • glia • nitric oxide