Seizures induce tenascin-C mRNA expression in neurons.
Tenascin-C, an extracellular matrix glycoprotein that exhibits both growth-promoting and growth-inhibiting properties, is produced in the CNS mainly by astrocytes. In the present study we show that kainate-induced seizures result in an increased expression of tenascin-C in rat brain. Tenascin-C mRNA was increased mainly in the granule cell layer of the hippocampal complex, but tenascin-C mRNA expression was also observed in the pyriform cortex and amygdalo-cortical nucleus. Double labelling experiments using tenascin-C probes and MAP2 (a neuronal microtubule associated protein) antibodies revealed many neurons in these layers that express tenascin-C mRNA. These results support our previous findings of an increased tenascin-C immunoreactivity associated with the axons of granule cells. Tenascin-C expression is rapidly induced by seizures (6 h), preceding any lesion and glial reaction. In this pathological condition tenascin-C appears to be produced by both glia and neurons. The functional repercussions on the scarring and remodelling processes are also discussed.
Université René Descartes, Paris V, INSERM U29, France.
L
L
Ferhat
N
N
Chevassus-Au-Louis
M
M
Khrestchatisky
Y
Y
Ben-Ari
A
A
Represa
D000818:Animals; D001345:Autoradiography; D018690:Excitatory Amino Acid Agonists; D005786:Gene Expression Regulation / Q000502:physiology; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006624:Hippocampus / Q000166:cytology; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007608:Kainic Acid; D008297:Male; D008869:Microtubule-Associated Proteins / Q000032:analysis; D009457:Neuroglia / Q000737:chemistry; D009474:Neurons / Q000737:chemistry / Q000502:physiology*; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012640:Seizures / Q000139:chemically induced / Q000503:physiopathology*; D019063:Tenascin / Q000032:analysis / Q000235:genetics*
D018690:Excitatory Amino Acid Agonists; D005904:Glial Fibrillary Acidic Protein; D008869:Microtubule-Associated Proteins; D012333:RNA, Messenger; D019063:Tenascin; D007608:Kainic Acid