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VIP and PACAP 38 modulate ibotenate-induced neuronal heterotopias in the newborn hamster neocortex.
- Source :
-
Journal of neuropathology and experimental neurology [J Neuropathol Exp Neurol] 2000 Dec; Vol. 59 (12), pp. 1051-62. - Publication Year :
- 2000
-
Abstract
- Intracerebral administration of ibotenate produces, through activation of N-methyl-D-aspartate (NMDA) receptors, neuronal heterotopias in the newborn hamster neocortex: high doses of ibotenate induce periventricular and subcortical neuronal heterotopias, while low doses of ibotenate produce intracortical heterotopias and molecular layer ectopias. Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) are closely related peptides with neurotrophic properties. They share common VPAC1 and VPAC2 receptors, which use cAMP as a second messenger. Previous studies have shown that VIP prevents excitotoxic neuronal death and exacerbates glutamate-induced c-fos neuronal expression. In order to gain new insight into the molecular control of neuronal migration, the present study examined the effects of VIP and PACAP on ibotenate-induced heterotopias in the newborn hamster. Co-treatment with VIP and a high dose of ibotenate produced a pattern of neuronal heterotopias similar to the one observed in animals treated with low doses of ibotenate alone. Pups co-injected with a low dose of ibotenate and a VIP antagonist displayed cortical dysgeneses similar to those observed in animals treated with high doses of ibotenate alone. The modulating effects of VIP on excitotoxin-induced heterotopias were mimicked by forskolin, PACAP, and by a specific VPAC2 receptor agonist but not by a VPAC1 agonist, and were blocked by a protein kinase A (PKA) inhibitor. Taken together, these data suggest that VIP and PACAP can attenuate ibotenate-induced heterotopias in newborn hamster and that this effect is mediated by the VPAC2 receptor utilizing the cAMP-PKA pathway.
- Subjects :
- Animals
Binding Sites
Choristoma chemically induced
Choristoma pathology
Cricetinae
Drug Synergism
Ibotenic Acid
Mesocricetus
Neocortex drug effects
Neocortex metabolism
Pituitary Adenylate Cyclase-Activating Polypeptide
Vasoactive Intestinal Peptide metabolism
Animals, Newborn physiology
Brain Diseases pathology
Choristoma prevention & control
Neocortex pathology
Nerve Tissue
Neuropeptides pharmacology
Vasoactive Intestinal Peptide pharmacology
Subjects
Details
- Language :
- English
- ISSN :
- 0022-3069
- Volume :
- 59
- Issue :
- 12
- Database :
- MEDLINE
- Journal :
- Journal of neuropathology and experimental neurology
- Publication Type :
- Academic Journal
- Accession number :
- 11138925
- Full Text :
- https://doi.org/10.1093/jnen/59.12.1051