Abstract
Purpose::
To test for apoptotic photoreceptor cell death and ceramide generation as a function of time following experimental retinal detachment.
Methods::
We induced a unilateral retinal detachment on White New Zealand rabbits using a subretinal injection of sodium hyaluronate. Both eyes were removed on days 1, 3 and 6 for anatomopathological and biochemical examinations. We counted the number of photoreceptors in histological sections, evaluated the level of apoptosis using the TUNEL assay method and analyzed the presence of ceramide in situ via an immunohistochemical study. The concentration of ceramide was also measured using a diacylglycerol kinase assay of retinal homogenate.
Results::
The average number of photoreceptors diminished regularly as a function of time after retinal detachment. The quantity of photoreceptors in apoptosis remained constant as a function of time (14%). In comparison to the control, the detached retina showed a high intensity of immunostaining by antibodies against ceramide. The concentration of intracellular, intra-retinal ceramide increased by 25% on day 3, following retinal detachment.
Conclusions::
Apoptotic photoreceptor cell death in experimental retinal detachments is probably associated with production of ceramide, the proapoptotic lipid.
Keywords: apoptosis/cell death • retinal detachment