Synaptic Development and Related Disturbances*

Abstract

Characteristics of synaptic development are as follows: 1) an increasedecrease in the number of synapses consisting of an over-production followed by elimination, the end product being the maturing form; 2) with maturation, there is a transformation from the axo-dendritic shaft synapses to the axo-dendritic spine ones. In early development, synaptogenesis probably proceeds simultaneously with myelination. A suggestion that the critical period giving definitive impairments in the organization of synapses exists may be raised. Quantitative analyses of the mitochondria1 number in the presynapse, determined using conventional osmium tetroxide staining and the number of synaptic junction determined using the EPTA preferential procedure reveal the synaptic changes, both in normal development or in response to nutritional and pharmacological factors.

Ultracytochemical analysis of E-PTA-positive synaptic junction. Three cases of Down's syndrome together with Alzheimer-type dementia.

“…However, Inomata et al (16,17) noted synaptic perforations in both the alcohol-treated and in the control rats, which were determined by using the experimental model for fetal alcohol syndrome.…”