Measurement of 5-hydroxytryptamine release in the rat medial vestibular nucleus using in vivo microdialysis.
The function of the 5-hydroxytryptamine (5-HT) system in the medial vestibular nucleus (MVN) was evaluated using KCl-evoked 5-HT release assessed by in vivo microdialysis. The release of 5-HT in the MVN was increased by the local application of KCl (100 mM) in a calcium-dependent manner. Likewise, perfusion of a 5-HT reuptake blocking agent, clomipramine (1 microM), increased extracellular levels of 5-HT in the MVN. Finally, pretreatment with the selective 5-HT(1A) agonist, 8-hydroxy-2-(di-N-propylamino) tetralin (1 mg/kg, intraperitoneally), attenuated the KCl-evoked 5-HT release. These findings suggest that 5-HT stored in vesicles is released from nerve terminals in the MVN. In addition, its regulation may be mediated by control of somatodendritic 5-HT(1A) receptor activation.
Inoue
Shino
S
Department of Otolaryngology, Nara Medical University, 840 Shijo-cho, Kashihara, Nara 634-8522, Japan.
Kita
Taizo
T
Yamanaka
Toshiaki
T
Ogawa
Yohichi
Y
Nakashima
Toshikatsu
T
Hosoi
Hiroshi
H
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000818:Animals; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D002997:Clomipramine / Q000494:pharmacology; D005110:Extracellular Space / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D017551:Microdialysis; D011189:Potassium Chloride / Q000494:pharmacology; D017729:Presynaptic Terminals / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*; D015854:Up-Regulation / Q000187:drug effects / Q000502:physiology; D014726:Vestibular Nuclei / Q000187:drug effects / Q000378:metabolism*
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D002997:Clomipramine; D011189:Potassium Chloride; D012701:Serotonin; D017366:Serotonin Receptor Agonists; D017367:Selective Serotonin Reuptake Inhibitors