[Optic nerve fibers and experimental diabetes].

OBJECTIVE

The main goal of this work was to determine the alterations that the optic nerve fibers of the experimentation animal undergo when diabetes is caused by means of an intraperitoneal streptozotocin injection. We try to compare the morphometric and morphological features of the nerve fibers of ill animals and those of healthy animals, according to the temporal evolution of the illness.

METHODS

24 two-month-old Sprague Dawley rats were studied. Diabetes was induced into half the rats and the rest were left as control ones. Six weeks later, half the animals of each group were sacrificed, and the other half twelve weeks after having started the experimentation. Both optic nerves were extracted in each animal and a morphometric and morphological study were carried out by means of electron microscopy.

RESULTS

We observed a delay in the growth of nerve fibers of diabetic animals in relation to the healthy ones, as well as morphological alterations which suggest degeneration and death of a certain number of fibers in diabetic animals.

CONCLUSIONS

Experimental diabetes causes, not only a certain degree of axonal degeneration in the optic nerve fibers, but also a delay in their growth.