APV PREVENTS THE ELIMINATION OF TRANSIENT DENDRITIC SPINES ON A POPULATION OF RETINAL GANGLION-CELLS

Blockade of the N-methyl-D-aspartate (NMDA) receptors on retinal ganglion cells (RGCs) during development prevents the elimination of the exuberant spine-like processes in a population of Type I RGCs in hamsters. During the development of RGCs, exuberant dendritic spines have been observed which disappear during maturation. Blocking the NMDA receptors on developing RGCs with the antagonist, DL-2-amino-5-phos-phonovaleric acid (APV) and the subsequent retention of some of the normally transient dendritic spines suggest that the morphological development of post-synaptic neurons may be affected by this treatment. Our result further suggests that the elimination of exuberant spines during normal development requires interactions between receptors on the spines and neurotransmitters released by the pre-synaptic inputs.