L. Acarin et al., Expression of growth inhibitory factor (metallothionein-III) mRNA and protein following excitotoxic immature brain injury, J NE EXP NE, 58(4), 1999, pp. 389-397
Citations number
48
Categorie Soggetti
Neurosciences & Behavoir
Journal title
JOURNAL OF NEUROPATHOLOGY AND EXPERIMENTAL NEUROLOGY
The balance between trophic factors and inhibitory molecules is likely to d
etermine the outcome of neural tissue damage. The growth inhibitory factor
(GIF), a member of the metallothionein family of proteins named metallothio
nein-Itt (Mf-III), has been suggested to play an important role in tissue r
epair after adult brain injury. Because no information is available on this
factor in relation to immature brain damage, we examined the chronological
changes of GIF (MT-III) mRNA and protein following excitotoxic lesions to
the postnatal day 9 brain using in situ hybridization and immunocytochemica
l techniques. We observed a significant decrease of neuronal GIF (MT-III) m
RNA and protein levels between 4 and 24 hours postinjury and an increase in
glial GIF (MT-III) levels. Double immunocytochemical techniques showed GIF
(MT-III) and GFAP positive astrocytes from 2-4 hours postinjury. From 3 da
ys postinjury strongly reactive astrocytes expressed strong levels of both
GIF (MT-III) mRNA and protein, which were maintained in the glial scar form
ed at longer times. These results show the expression of an inhibitory mole
cule by postnatal reactive astrocytes. Glial GIF (MT-III) expression may pl
ay an important role in the tissue reconstruction after immature brain dama
ge.