HRP-HISTOCHEMICAL DETECTION OF RETINAL PROJECTIONS TO THE HYPOTHALAMUS IN NEONATAL RATS

Abstract

We examined retinal projections to the hypothalamus in albino rats at early postnatal stages by means of injecting horseradish peroxidase (HRP) into the eye and observing the anterograde transport. On the 1st postnatal day, HRP-filled retinal fibers reached the suprachiasmatic nucleus (SCN) on the bilateral sides to the eye injection of HRP, and made synaptic connections with dendrites of the SCN neurons. The retinal projection to the lateral hypothalamic area (LHA) on the contralateral side to the eye injection of HRP was also noted at the 1st and 3rd postnatal days, but not on the 7th and 10th postnatal days or in the adults.