Postnatal development of synaptic populations within the ciliary ganglion of the rat.
Date
1992
Authors
Robertson, George Norman.
Journal Title
Journal ISSN
Volume Title
Publisher
Dalhousie University
Abstract
Description
There is evidence of a post-natal refinement of neural connections in mammalian autonomic ganglia; the number of inputs decreases as the number of synapses increases. This suggests a selective change in the strength of connections as some are eliminated while others consolidate the connection by synaptogenesis. To determine if changes in connection strength are manifest in structural changes to the synapses, a morphological investigation of the synapse populations within the ciliary ganglion was performed on 1, 3 and 8 week old rats.
The axosomatic synapse population increases four-fold between 1 and 3 weeks of age due to the differential formation and/or retention of one specific synapse type--the somatic spine. This may be due to its relative simplicity of construction, allowing an axon greater access to post-synaptic target territory in less time.
During this same period, synapses become preferentially located on the area of neural cell body membrane that is associated with the perinuclear portion of the overlying glial cell. The glial cell may aid in the maintenance of connection by reducing the risk of elimination. Alterations of the synapse population caused by these changes are maintained in the adult, suggesting they act to stabilize synaptic connections.
Thesis (Ph.D.)--Dalhousie University (Canada), 1992.
The axosomatic synapse population increases four-fold between 1 and 3 weeks of age due to the differential formation and/or retention of one specific synapse type--the somatic spine. This may be due to its relative simplicity of construction, allowing an axon greater access to post-synaptic target territory in less time.
During this same period, synapses become preferentially located on the area of neural cell body membrane that is associated with the perinuclear portion of the overlying glial cell. The glial cell may aid in the maintenance of connection by reducing the risk of elimination. Alterations of the synapse population caused by these changes are maintained in the adult, suggesting they act to stabilize synaptic connections.
Thesis (Ph.D.)--Dalhousie University (Canada), 1992.
Keywords
Biology, Anatomy., Biology, Neuroscience.