PMID- 18512214
OWN - NLM
STAT- MEDLINE
DCOM- 20081020
LR  - 20131121
IS  - 0887-4476 (Print)
IS  - 0887-4476 (Linking)
VI  - 62
IP  - 8
DP  - 2008 Aug
TI  - Serotoninergic dorsal raphe neurons possess functional postsynaptic nicotinic 
      acetylcholine receptors.
PG  - 601-15
LID - 10.1002/syn.20526 [doi]
AB  - Very few neurons in the telencephalon have been shown to express functional 
      postsynaptic nicotinic acetylcholine receptors (nAChRs), among them, the 
      noradrenergic and dopaminergic neurons. However, there is no evidence for 
      postsynaptic nAChRs on serotonergic neurons. In this study, we asked if 
      functional nAChRs are present in serotonergic (5-HT) and nonserotonergic 
      (non-5-HT) neurons of the dorsal raphe nucleus (DRN). In rat midbrain slices, 
      field stimulation at the tegmental pedunculopontine (PPT) nucleus evoked 
      postsynaptic currents (eEPSCs) with different components in DRN neurons. After 
      blocking the glutamatergic and GABAergic components, the remaining eEPSCs were 
      blocked by mecamylamine and reduced by either the selective alpha7 nAChR 
      antagonist methyllycaconitine (MLA) or the selective alpha4beta2 nAChR antagonist 
      dihydro-beta-eritroidine (DHbetaE). Simultaneous addition of MLA and DHbetaE 
      blocked all eEPSCs. Integrity of the PPT-DRN pathway was assessed by both 
      anterograde biocytin tracing and antidromic stimulation from the DRN. Inward 
      currents evoked by the direct application of acetylcholine (ACh), in the presence 
      of atropine and tetrodotoxin, consisted of two kinetically different currents: 
      one was blocked by MLA and the other by DHbetaE; in both 5-HT and non-5-HT DR 
      neurons. Analysis of spontaneous (sEPSCs) and evoked (eEPSCs) synaptic events led 
      to the conclusion that nAChRs were located at the postsynaptic membrane. The 
      possible implications of these newly described nAChRs in various physiological 
      processes and behavioral events, such as the wake-sleep cycle, are discussed.
FAU - Galindo-Charles, Luis
AU  - Galindo-Charles L
AD  - Department of Physiology, College of Medicine, Universidad Nacional Autonoma de 
      Mexico, Mexico D.F. 04510.
FAU - Hernandez-Lopez, Salvador
AU  - Hernandez-Lopez S
FAU - Galarraga, Elvira
AU  - Galarraga E
FAU - Tapia, Dagoberto
AU  - Tapia D
FAU - Bargas, Jose
AU  - Bargas J
FAU - Garduno, Julieta
AU  - Garduno J
FAU - Frias-Dominguez, Carmen
AU  - Frias-Dominguez C
FAU - Drucker-Colin, Rene
AU  - Drucker-Colin R
FAU - Mihailescu, Stefan
AU  - Mihailescu S
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Synapse
JT  - Synapse (New York, N.Y.)
JID - 8806914
RN  - 0 (Chrna7 protein, rat)
RN  - 0 (Nicotinic Antagonists)
RN  - 0 (Receptors, Nicotinic)
RN  - 0 (alpha7 Nicotinic Acetylcholine Receptor)
RN  - 0 (nicotinic receptor alpha4beta2)
RN  - 333DO1RDJY (Serotonin)
RN  - N9YNS0M02X (Acetylcholine)
SB  - IM
MH  - Acetylcholine/metabolism
MH  - Animals
MH  - Electric Stimulation
MH  - Excitatory Postsynaptic Potentials/drug effects/physiology
MH  - Mesencephalon/*metabolism
MH  - Neural Pathways/drug effects/metabolism
MH  - Neurons/drug effects/*metabolism
MH  - Nicotinic Antagonists/pharmacology
MH  - Organ Culture Techniques
MH  - Patch-Clamp Techniques
MH  - Pedunculopontine Tegmental Nucleus/metabolism
MH  - Raphe Nuclei/cytology/drug effects/*metabolism
MH  - Rats
MH  - Rats, Wistar
MH  - Receptors, Nicotinic/drug effects/*metabolism
MH  - Serotonin/*metabolism
MH  - Synapses/drug effects/metabolism
MH  - Synaptic Membranes/drug effects/metabolism
MH  - Synaptic Transmission/drug effects/*physiology
MH  - Wakefulness/drug effects/physiology
MH  - alpha7 Nicotinic Acetylcholine Receptor
EDAT- 2008/05/31 09:00
MHDA- 2008/10/22 09:00
CRDT- 2008/05/31 09:00
PHST- 2008/05/31 09:00 [pubmed]
PHST- 2008/10/22 09:00 [medline]
PHST- 2008/05/31 09:00 [entrez]
AID - 10.1002/syn.20526 [doi]
PST - ppublish
SO  - Synapse. 2008 Aug;62(8):601-15. doi: 10.1002/syn.20526.