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Changes in neurotransmitter uptake in the spinal cord following peripheral nerve injury
Author(s) -
Somps Christopher J.,
Boyajian Christine L.,
Luttges Marvin W.
Publication year - 1988
Publication title -
synapse
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.809
H-Index - 106
eISSN - 1098-2396
pISSN - 0887-4476
DOI - 10.1002/syn.890020202
Subject(s) - spinal cord , neurochemical , compartmentalization (fire protection) , neurotransmitter , glutamate receptor , chemistry , sciatic nerve , neurotransmission , neuroscience , spinal cord injury , endocrinology , medicine , anesthesia , anatomy , central nervous system , biology , biochemistry , receptor , enzyme
Changes in neurotransmitter systems of the spinal cord were studied in response to peripheral nerve injury. The uptake and compartmentalization of radiolabeled spinal cord neurotransmitters and transmitter precursors were examined as a function of time following unilateral sciatic nerve crush in adult mice. Accumulation of transmitter was measured within synaptosomally enriched fractions prepared using combinations of differential and density gradient centrifugations. The amount of transmitter substance recovered from these fractions was strongly depedent upon the amount of time following nerve injury and on the specific transmitter or precursor being examined (GABA, glutamate, glycine, and choline chloride). However, for each of these substances, uptake values returned to control levels within nine to twelve days after nerve crush. Localization of GABA changes postcrush revealed reciprocal differences between ipsilateral and contralateral sides of the spinal cord, as well as differences between segmental levels. Altered GABA uptake may reflect changes in the postcrush microchemical environment present during tissue processing, but may also be related to direct changes in the synaptic binding, transport, and compartmentalization of transmitter substance. The time course, magnitude, and direction of these neurochemical changes follow those observed neurophysiologically, and may thus underlie injury‐induced short‐term (days) alterations reported in primary afferent depolarizations, cross cord responses, and other spinal mechanisms.