The less energy produced by mitochondrion in retina's internal reticular layer shows the inactivity of the ganglion cell.

Glaucoma is a chronic optic neuropathy characterized by retinal ganglion cell death resulting in damage to the optic nerve head and the retinal nerve fiber layer.

The expression of VIP exists on photoreceptor- outer segment, inner nuclear layer and inner plexiform layer of retina and choroids, and weak expression exists on ganglion cell and nerve fiber layer.