Objective: To evaluate the effect of pressures on the changes of purified cultivation of SD suckling rats' retinal ganglion cells (RGC) by a hyperbaric cell culture model and on the expression of neurofilament protein-H (NF-H) in vitro.
Methods: It was a control experimental study. RGC were purified from twenty SD neonatal rats (postnatal 1 - 3 days) using Thy1.1 antibody and cultured under the pressures of 0, 20, 40, 60, and 80 mm Hg (1 mm Hg = 0.133 kPa) respectively. The growth and survival times of RGC were observed, the numbers of processes of RGC were counted, and the processes measured under the different pressures after 48 h under phase-contrast microscope. The expression of NF-H and its distribution in primary purified RGC was investigated by an immunohistochemical technique and by semi-quantitative statistics analysis using microscopic image-analysis technique. The data was analyzed with SPSS 13.0 software. Difference among groups with One-way ANOVA and ambi-groups with SNK (q test), statistical significance was confirmed as P < 0.05.
Results: The purification rate of RGC reached 96.24% after cultured for 12 hours. Compared with the control group, the growth and survival times of RGC were similar (P = 0.595, 0.147) under the pressure of 20 mm Hg cultured for 48 hours, the expression of NF-H in RGC was not different (P = 0.227); but the growth and survival times of RGC were significantly different (P = 0.001, 0.000, 0.000 and 0.000, 0.000, 0.000) under the pressures of 40, 60, and 80 mm Hg, respectively. The expression of NF-H in RGC were significantly (P = 0.000, 0.000, 0.000) reduced under the pressures of 40, 60, and 80 mm Hg for 48 hours respectively.
Conclusions: The growth and survival times of cultured RGC in vitro are affected by the pressure > 40 mm Hg leading to a decreased expression of NF-H indicating a pressure caused mechanism of RGC damage in glaucoma. Down-regulation of NF-H may influence the process growth of RGC.