Effects of a chronic myositis on structural and functional features of spinal astrocytes in the rat.
The study aimed at the question if astrocytes react with morphological or functional changes when a skeletal muscle is pathologically altered. In rats, a myositis was induced in the gastrocnemius-soleus muscle. After 12 days, the immunoreactivity (IR) for glial fibrillary acidic protein (GFAP), morphometric parameters, and fibroblast growth factor-2 (FGF-2) expression of astrocytes were quantitatively evaluated in the dorsal horn of the spinal segment L4. Following inflammation, the area density of GFAP-IR as well as the proportion of astrocytes expressing FGF-2 increased significantly while the degree of astrocyte arborisation decreased as shown by a shape factor. The density of cell nuclei was unchanged suggesting that no myositis-induced cell divisions occurred. The data indicate that spinal astrocytes may influence pain processes particularly by increased FGF-2 synthesis.
Tenschert
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S
Institut für Anatomie und Zellbiologie, Universität Heidelberg, Im Neuenheimer Feld 307, D-69120 Heidelberg, Germany.
Reinert
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A
Hoheisel
U
U
Mense
S
S
D000344:Afferent Pathways / Q000503:physiopathology*; D000818:Animals; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology*; D048429:Cell Size / Q000502:physiology; D002908:Chronic Disease; D004195:Disease Models, Animal; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D018482:Muscle, Skeletal / Q000294:innervation / Q000503:physiopathology; D009220:Myositis / Q000473:pathology* / Q000503:physiopathology; D010146:Pain / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology; D020671:Posterior Horn Cells / Q000473:pathology / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000473:pathology* / Q000503:physiopathology; D015854:Up-Regulation / Q000502:physiology
D005904:Glial Fibrillary Acidic Protein; D016222:Fibroblast Growth Factor 2