Metabolic activity changes in the rat spinal cord during adjuvant monoarthritis

• Type: Article in International Scientific Journal
• Date: 1999

Authors

Schadrack, J (Author) Other; Neto F.L. (Author) Other; Ableitner, A (Author) Other; Castro-Lopes J.M. (Author) FMUP; Willoch, F (Author) Other; Bartenstein, P (Author) Other; Zieglgansberger, W (Author) Other; Tolle, TR (Author) Other

Journal

Title: Neuroscience

Vol. 94 No. 2

Pages: 595-605

ISSN: 0306-4522

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 49 Citations

Scopus - 54 Citations

Pubmed / Medline

Other information

Authenticus ID: P-001-61F

DOI: 10.1016/s0306-4522(99)00186-4

Abstract (EN): The development of chronic pain is associated with activity-dependent plastic changes in neuronal structures in the peripheral and central nervous system. In order to investigate the time-dependent processing of afferent noxious stimuli in the spinal cord we employed the quantitative autoradiographic 2-deoxyglucose technique in a model of chronic monoarthritic pain in the rat. Spinal metabolic activity was determined at various time-points (two, four and 14 days) after the injection of complete Freund's adjuvant into the left tibiotarsal joint. In addition, the effect of acute noxious mechanical stimulation of the arthritic joint was investigated at 14 days of monoarthritis. Local glucose utilization was determined in lumbar segments L-2-L-5, ipsi- and contralateral to the inflamed hindpaw, and compared with saline-injected controls, in general, monoarthritic animals had bilaterally increased metabolic activity in all laminae of the spinal cord. Detailing the time-course showed that in rats with two days of monoarthritis metabolic activity was significantly increased to a similar extent on both sides of all spinal laminae. In contrast, at four days, glucose utilization in deep laminae of the dorsal horn (laminae V-VI), the central gray area (laminae X) and the ventral horn (laminae W-M) tended to return to control levels. At 14 days of monoarthritis, however, metabolic activity showed a further increase in all laminae of the spinal cord. This increase was more pronounced on the side ipsilateral to inflammation, reaching 65% above corresponding control levels in laminae V, VI. Animals with 14 days of monoarthritis which were subjected to mechanical noxious stimulation of the arthritic joint displayed clear behavioral signs of acute pain. Although in this group metabolic activity was above control levels, it was lower than in animals with 14 days of monoarthritis that were not additionally stimulated. The data show not only a general increase of spinal cord metabolic activity during the time-course of the development of a chronic pain state, but also show a region-specific non-linear time profile. This may reflect the complexity of transducing and suppressive transmitter systems involved in the central processing of ongoing pain. (C) 1999 IBRO. Published by Elsevier Science Ltd.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 11