Effects of Denervation and Axotomy on Nervous System-Specific Protein, Ornithine Decarboxylase, and Other Enzyme Activities in the Superior Cervical Sympathetic Ganglion of the Rat

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Abstract
The time courses of changes of 3 enolase isozymes (.alpha..alpha., .alpha..gamma. and .gamma..gamma.), S-100 protein, 2'',3''-cyclic nucleotide 3''-phosphodiesterase (CNPase), ornithine decarboxylase (ODC), .beta.-galactosidase, and G-6-P dehydrogenase (G6PDH) were examined from 1-14 days after cutting of the preganglionic nerve (denervation) or the postganglionic nerve (axotomy) of the superior cervical sympathetic ganglion (SCG) of the rat. The wet weight and protein content in the axotomized SCG increased for 1-2 wk after the operations. Among enolase isozymes in the SCG, neuron-specific .gamma..gamma.-enolase decreased rapidly after denervation and stayed at a low level for 2 wk, whereas the isozyme remained almost unchanged after axotomy. Ganglionic .alpha..alpha.-enolase and the .alpha..gamma.-hybrid form increased remarkably to reach a maximum at the 2nd day after axotomy and remained above control for 1-2 wk; these 2 enolase isozymes showed little change after denervation. Denervation caused a much larger increase than did axotomy in the ganglionic S-100 protein, an astrocyte-specific protein, during the 1st wk after the operation. The protein content decreased after 2 wk of either denervation or axotomy. CNPase, a myelin-associated enzyme, rose suddenly 2 days after axotomy, and remained at a rather high level compared with the denervated ganglion, which showed little variation. Ornithine decarboxylase, a rate-limiting enzyme catalyzing polyamine biosynthesis, which participates in the regulation of growth and differentiation of the cells, increased significantly within 2-4 days after axotomy and then decreased to a subcontrol level after the next wk; the enzyme activity changed a gradual decrease of a neuronal marker enzyme, .beta.-galactosidase activity, but produced an increase of G6PDH, an enzyme essential in lipid biosynthesis for myelin formation.