NEURONS PROJECTING TO THE HYPOTHALAMUS FROM THE BRAIN-STEM A1-CATECHOLAMINERGIC CELL GROUP EXPRESS GLUTAMATE R2,3-RECEPTOR IMMUNOREACTIVITY

Authors
Citation
Pj. Larsen et N. Vrang, NEURONS PROJECTING TO THE HYPOTHALAMUS FROM THE BRAIN-STEM A1-CATECHOLAMINERGIC CELL GROUP EXPRESS GLUTAMATE R2,3-RECEPTOR IMMUNOREACTIVITY, Brain research, 705(1-2), 1995, pp. 209-215
Citations number
31
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Neurosciences
Journal title
Brain research → ACNP
ISSN journal
0006-8993
Volume
705
Issue
1-2
Year of publication
1995
Pages
209 - 215
Database
ISI
SICI code
0006-8993(1995)705:1-2<209:NPTTHF>2.0.ZU;2-Z
Abstract
Stimulation of ascending catecholaminergic neurones of the Al region i n ventrolateral medulla by excitatory amino acids mediate neurohypophy sial vasopressin secretion triggered by hypovolemic hypotension. Recen t cloning of the ionotrophic excitatory amino acid receptors of the al pha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)-type an d subsequent production of receptor recognizing antisera have made imm unocytochemical detection of receptor proteins in phenotypically chara cterized neurones possible. Using single immunocytochemical detection of glutamate GluR1, GluR2,3, GluR4 receptor proteins we have investiga ted the distribution of GluR-receptor proteins in the caudal ventrolat eral medulla. In the neurones of the Al cell group, only GluR2,3-immun oreactivity was expressed whereas GluR1-immunoreactive neurones were s een in the adjacent reticular formation. Using dual immunocytochemistr y in combination with retrograde Fluorogold tracing we determined the extent of co-expression of tyrosine-hydroxylase and glutamate GluR2,3 receptor protein immunoreactivity in neurones of the Al cell group in the ventrolateral medulla that project to the area of the paraventricu lar nucleus of the hypothalamus. It was seen that the majority of cate cholaminergic Al neurones of the caudal VLM that project directly to t he paraventricular nucleus are also immunoreactive to the Glu R2,3 rec eptor protein further substantiating that these neurones are directly influenced by the excitatory amino acid glutamate.