Retinal ganglion cell death in experimental glaucoma and after axotomy occurs by apoptosis.
OBJECTIVE
To investigate whether retinal ganglion cell death in experimental glaucoma and after axotomy occurs by apoptosis.


METHODS
Chronic elevated eye pressure was produced in 20 monkey eyes, and the optic nerve was transected unilaterally in the orbit of 10 monkeys and 14 rabbits. Sixteen monkey and 14 rabbit eyes were studied as normal controls. Analytic methods included light and electron microscopy, histochemistry for DNA fragmentation (TUNEL method), and DNA electrophoresis in agarose gels.


RESULTS
Dying ganglion cells in the experimental retinas exhibited morphologic features of apoptosis, including chromatin condensation and formation of apoptotic bodies. Cells with a positive reaction for DNA fragmentation were observed in eyes subjected to axotomy and experimental glaucoma but were only rarely encountered in control eyes. No evidence of internucleosomal fragmentation was detected electrophoretically, possibly because of the small proportion of cells that were dying at any given time.


CONCLUSIONS
Some retinal ganglion cells injured by glaucoma and by axotomy die by apoptosis.
Quigley
H A
HA
Department of Ophthalmology, Wilmer Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.
Nickells
R W
RW
Kerrigan
L A
LA
Pease
M E
ME
Thibault
D J
DJ
Zack
D J
DJ
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D001369:Axons / Q000502:physiology*; D016923:Cell Death; D004247:DNA / Q000032:analysis; D004249:DNA Damage / Q000502:physiology; D004195:Disease Models, Animal; D004587:Electrophoresis, Agar Gel; D005260:Female; D005901:Glaucoma / Q000473:pathology / Q000503:physiopathology*; D008252:Macaca fascicularis; D008297:Male; D009410:Nerve Degeneration / Q000502:physiology; D009900:Optic Nerve / Q000601:surgery; D011817:Rabbits; D012165:Retinal Ganglion Cells / Q000502:physiology* / Q000648:ultrastructure
D004247:DNA