Table 2. Raw C_t values and relative expression levels for GAPDH and OPA1 in differentiated RGC-5 cells following elevated hydrostatic pressure.

Group number	Time	Passage number	Conditions	Ct values GAPDH	Ct values OPA1	ΔCt	ΔΔCt	Relative expression
1	Day 2	34	Control	17.06	28.81	11.75	−0.57	Upregulation by 47.6%
			30 mmHg	18.82	30	11.18
	Day 3		Control	17.96	29.17	11.21	0.62	Down-regulation by 37.5%
			30 mmHg	17.85	29.68	11.83
2	Day 2	28	Control	16.82	28.36	11.54	−0.48	Upregulation by 36.5%
			30 mmHg	16.82	27.88	11.06
	Day 3		Control	16.94	27.87	10.93	0.68	Down-regulation by 37.7%
			30 mmHg	17.35	28.96	11.61
3	Day 2	30	Control	16.98	28.34	11.36	−0.27	Upregulation by 20.6%
			30 mmHg	16.84	27.93	11.09
	Day 3		Control	18.16	28.51	10.35	0.5	Down-regulation by 31.5%
			30 mmHg	18.51	29.36	10.85

This table showed that expression for GAPDH and OPA1 was not dependent with passage number and GAPDH did not change with elevated hydrostatic pressure. The negative ∆∆C_t represents upregulation of gene expression and the positive ∆∆C_t represents down-regulation of gene expression.