[Ultrastructural changes of the retinal pigment epithelium in pigs fed with a fat rich diet].

PURPOSE

To determine if the intake of a rich diet is related to ultraestructural changes and with an increase in lipofuscin accumulation in porcine retinal pigment epithelium (RPE).

METHODS

The animals were divided into two groups of 6 pigs each. In the first group (control), a restricted diet of chow mix was supplied. The second group (fat-fed group) was fed with the same type of nutritional diet, however one third of the food was replaced by saturated fatty acid. Total cholesterol, HDL, LDL, and triglycerides were determined at the beginning and at the end of the experiment. After 12 weeks, the eyes were enucleated and the RPE structure was examined by electron microscopy.

RESULTS

No significant differences were observed in the RPE lipofuscin accumulation between the control group and the fat-fed group (p=0.3). However, morphological disorders such as nuclear pyknosis, accumulation of electron dense particles in Bruch's membrane, and the accumulation of empty and lipid-like vacuoles in the cytoplasm were observed in the RPE of the fat-fed group but not in the control animals.

CONCLUSIONS

The ultrastructural changes observed in the porcine RPE can be related to a high fat diet to the increase in lipid plasma levels.