EFFECTS OF PRENATAL COCAINE EXPOSURE IN THE PHOTORECEPTOR CELLS OF THE RAT RETINA

Despite the increasing evidence of eye abnormalities, the effects of p renatal exposure to cocaine on the visual system are still poorly unde rstood. This study was aimed at analyzing the qualitative and quantita tive organization of the retinal photoreceptor cells (PR) and outer nu clear layer (ONL) after prenatal exposure to cocaine in the rat. Pregn ant Wistar rats were given sc injections of cocaine hydrochloride (60 mg/kg body wt/d) or saline or were not manipulated; analyses were perf ormed in the 14- and 30-d-old male offspring. Radial semithin and ultr athin sections of epon-embedded flat mounts of the retina showed displ aced PR-like cells in the inner nuclear layer (INL), picnotic PR nucle i in INL, and ONL, and retinal PR rosettes and outer-segment debris in the subretinal space. The quantitative study showed an increased dens ity of PR-like nuclei in the INL in PND14 cocaine-treated rats that we re within normal values at PND30; no changes were detected in the PR m ean nuclear diameter and in the packing density of PR nuclei in the ON L. These data constitute the first morphological demonstration of phot oreceptor damage after prenatal cocaine-exposure probably owing to a d irect action of the drug and/or to the cocaine-induced ischemia/hypoxi a.