The patterns of retinal ganglion cell death in hypertensive eyes

We have recently described a rat model of hypertensive eye in which cauterizing limbal derived episcleral veins leads to increase in the intraocular pressure [S.R. Shareef, E. Garcia-Valenzuela, A. Salierno, J. Walsh, S.C. Sharma, Chronic ocular hypertension following episcleral venous occlusion in rats, Exp. Eye Res. 61 (1995) 379-382.]. We have further documented that retinal ganglion cell death is apoptotic [E. Garcia-Valenzuela, S. Shareef, J. Walsh, S.C. Sharma, Programmed cell death of retinal ganglion cells during experimental glaucoma, Exp. Eye Res. 61 (1995) 33-44.]. Here, we describe the total loss of retinal ganglion cells at various time intervals following increased IOP. At early time points death of ganglion cells in the central, peripheral retina occurred with similar frequencies. Between 4-6 weeks after intraocular elevation, ganglion cells in the peripheral retina were more susceptible than the central retina. Percentage of total ganglion cell death over the 10 week period was presumably linear and was about 4% per week.