Increased expression of 5-HT(1B) receptors by Herpes simplex virus gene transfer in septal neurons: New in vitro and in vivo models to study 5-HT(1B) receptor function.
Serotonergic modulation of acetylcholine (ACh) release after neuron-specific increase of the expression of 5-HT(1B) receptors by gene transfer was studied in vitro and in vivo. The increased expression of the 5-HT(1B) receptor in vitro was induced by treating rat primary fetal septal cell cultures for 3 days with a viral vector inducing the expression of green fluorescent protein (GFP) vector alone, or, in addition, of 5-HT(1B) receptors (HA1B/GFP vector). The transfection resulted in a high number of GFP-positive cells, part of which being immunopositive for choline acetyltransferase. In HA1B/GFP-cultures (vs. GFP-cultures), electrically evoked ACh release was significantly more sensitive to the inhibitory action of the 5-HT(1B) agonist CP-93,129. Increased expression of the 5-HT(1B) receptor in vivo was induced by stereotaxic injections of the vectors into the rat septal region. Three days later, electrically evoked release of ACh in hippocampal slices of HA1B/GFP-treated rats was lower than in their GFP-treated counterparts, showing a higher inhibitory efficacy of endogenous 5-HT on cholinergic terminals after transfection. Moreover, CP-93,129 had a higher inhibitory potency. In conclusion, the HA1B/GFP vector reveals a useful tool to induce a targeted increase of 5-HT(1B) heteroreceptors on cholinergic neurons in selected CNS regions, which provides interesting perspectives for functional approaches at more integrated levels.
Riegert
Céline
C
Institut für Experimentelle und Klinische Pharmakologie und Toxikologie der Universität Freiburg, Neuropharmakologisches Labor, Hansastrasse 9A, D-79104 Freiburg, Germany.
Rothmaier
Anna Katharina
AK
Leemhuis
Jost
J
Sexton
Timothy J
TJ
Neumaier
John F
JF
Cassel
Jean-Christophe
JC
Jackisch
Rolf
R
D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D018929:Cell Culture Techniques; D002478:Cells, Cultured; D002799:Cholinergic Fibers / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation / Q000235:genetics; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000235:genetics*; D049452:Green Fluorescent Proteins / Q000235:genetics; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D009924:Organ Culture Techniques; D051381:Rats; D020318:Rats, Long-Evans; D017207:Rats, Sprague-Dawley; D044302:Receptor, Serotonin, 5-HT1B / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics; D012686:Septal Nuclei / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D018139:Simplexvirus / Q000235:genetics*; D015854:Up-Regulation / Q000235:genetics
D044302:Receptor, Serotonin, 5-HT1B; D011993:Recombinant Fusion Proteins; D017366:Serotonin Receptor Agonists; D049452:Green Fluorescent Proteins; D012701:Serotonin; D000109:Acetylcholine