[Apoptosis in ischemic optic neuropathy].
OBJECTIVE
A study of human eyes with non-arteritic ischaemic optic neuropathy (NAION) to determine whether there is apoptosis and whether this is accompanied by cell necrosis mechanisms.


METHODS
Transmission electron microscopy was used to examine the retinas of eyes with NAION.


RESULTS
There was a large number of apoptotic ganglion cells. The lesion was not confined to this retinal layer but also affected the inner nuclear layer, where Müller glia with fagocytic capacity were detected. In this layer apoptosis alternated with necrosis in all of the cell types existing in this level: bipolar cells, amacrine cells and horizontal cells. The outer nuclear layer can also suffer lesion, essentially by induction of choroid ischaemia to that level. Again, apoptosis was observed at the photoreceptor level, where there was also death by heterophagy, although this was less frequent.


CONCLUSIONS
The behaviour of NAION in humans is similar to that found in experimental models. Apoptosis mechanisms develop, alternating with cell necrosis in the nuclear level.
Salazar
J J
JJ
Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Facultad de Medicina, Universidad Complutense de Madrid, España. meci201@emducms1.sis.ucm.es
Ramírez
A I
AI
de Hoz R
Rojas
B
B
Triviño
A
A
Ramírez
J M
JM
D000368:Aged; D000369:Aged, 80 and over; D017209:Apoptosis; D002102:Cadaver; D006801:Humans; D008854:Microscopy, Electron; D008875:Middle Aged; D009900:Optic Nerve / Q000473:pathology / Q000648:ultrastructure; D018917:Optic Neuropathy, Ischemic / Q000473:pathology*