Publication Date
2017
Document Type
Thesis
Committee Members
David Ladle (Advisor), Mark Rich (Committee Member), Patrick Sonner (Committee Member)
Degree Name
Master of Science (MS)
Abstract
The monosynaptic stretch reflex circuit is one of the simplest circuits of the central nervous system. We studied the connection between Ia proprioceptive afferents and motor neurons that comprise the circuit, by stimulating the dorsal root and recording from the ventral root of the fourth lumbar spinal nerve. In our study, we analyzed the status of neurotransmission in the stretch reflex circuit in postnatal PV-cre; munc18-1 lox/lox conditional mutant mice. Munc18-1 is responsible for synaptic vesicular release in neurons. In the PV-cre; Munc18-1 lox/lox mutants we use, Munc18-1 is only knocked out in proprioceptive afferents and A-beta somatosensory afferents, both of which express parvalbumin (PV). Our results showed that on the first postnatal day (P1), responses evoked from the ventral root are significantly reduced in mutants compared to wild type mice. Similar results were also observed at P6. Our results lead us to conclude that PV-cre; Munc18-1 lox/lox mutant mice lack synaptic vesicular release in proprioceptive afferents after birth as evidenced by a dramatically reduced stretch reflex circuit response analyzed with the electrophysiology experiments in our study.
Page Count
35
Department or Program
Department of Neuroscience, Cell Biology and Physiology
Year Degree Awarded
2017
Copyright
Copyright 2017, some rights reserved. My ETD may be copied and distributed only for non-commercial purposes and may not be modified. All use must give me credit as the original author.
Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.
