Somato-dendritic distribution of 5-HT(1A) and 5-HT(1B) autoreceptors in the BDNF- and cAMP-differentiated RN46A serotoninergic raphe cell line.
The rapid differentiating effects of brain-derived neurotrophic factor (BDNF) or dibutyryl-cAMP (dBcAMP) were characterized on RN46A, a rat raphe-derived neuronal cell line. After BDNF treatment, RN46A cells were serotonin-immunopositive and bipolar, and expressed the microtubule-associated-protein 2 (Map2). After dBcAMP treatment, the cells often became multipolar, bearing very long processes strongly immunopositive for serotonin and Map2. Under both conditions, the expression and distribution of 5-HT(1A) and 5-HT(1B) autoreceptors remained identical. 5-HT(1A) and Map2 immunolabelings were superimposable, as expected of their somato-dendritic targeting. Surprisingly, the distribution of 5-HT(1B) immunoreactivity was similar, in contrast with its usual localization in axons and nerve terminals in the brain. In conclusion, both BDNF and cAMP-differentiated RN46A cells towards a neuronal serotoninergic-like phenotype without the typical differential targeting of the 5-HT(1) autoreceptors, an interesting model to study the molecular mechanisms ensuing the targeting of 5-HT(1) autoreceptors to somas and dendrites.
Laboratoire de Neurobiologie des Signaux Intercellulaires, CNRS UMR 7101, Université Pierre et Marie Curie, 75005 Paris, France.
Prakasham
P
Rumajogee
Daniel
D
Vergé
Michel
M
Hamon
Marie-Christine
MC
Miquel
D000818:Animals; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects*; D002460:Cell Line; D000242:Cyclic AMP / Q000494:pharmacology*; D003712:Dendrites / Q000378:metabolism; D007150:Immunohistochemistry / Q000379:methods; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009474:Neurons / Q000166:cytology* / Q000187:drug effects; D011903:Raphe Nuclei / Q000166:cytology*; D051381:Rats; D044282:Receptor, Serotonin, 5-HT1A / Q000378:metabolism*; D044302:Receptor, Serotonin, 5-HT1B / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism* / Q000494:pharmacology
D019208:Brain-Derived Neurotrophic Factor; C489787:MAP2 protein, rat; D008869:Microtubule-Associated Proteins; D044302:Receptor, Serotonin, 5-HT1B; D044282:Receptor, Serotonin, 5-HT1A; D012701:Serotonin; D000242:Cyclic AMP