Effects of 5-Hydroxytryptamine on Potassium Currents of the Medial Vestibular Nuclear Neuron in the Rat.
- Author:
Han Seong JEONG
1
;
Sun Hwa CHA
;
Myung Joo JANG
;
Yong Bum CHO
;
Jae Yeoul JUN
;
Jong Seong PARK
Author Information
1. Department of Physiology, Chosun University College of Medicine, Gwangju, Korea. parkjs@chonnam.ac.kr
- Publication Type:Original Article
- Keywords:
5-Hydroxytryptamine;
Potassium channels;
Vestibular nuclei
- MeSH:
Animals;
Digestion;
Dihydroergotamine;
Ether;
Membranes;
Neurons*;
Patch-Clamp Techniques;
Potassium Channels;
Potassium*;
Rats*;
Rats, Sprague-Dawley;
Serotonin 5-HT1 Receptor Agonists;
Serotonin 5-HT2 Receptor Agonists;
Serotonin*;
Vestibular Nuclei
- From:Korean Journal of Otolaryngology - Head and Neck Surgery
2003;46(11):915-921
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND AND OBJECTIVES: This study was aimed to explore the effects of the 5-hydroxytryptamine (5-HT) on potassium currents in rat vestibular nuclear neurons. MATERIALS AND METHOD: Sprague-Dawley rats aged 14 to 16 days were anesthetized with ether and decapitated. After enzymatic digestion, the portion of medial vestibular nucleus neuron was removed by micropunching and gently agitated. The dissociated neurons were transferred into a recording chamber mounted on an inverted microscope and whole-cell membrane currents were recorded at room temperature by using standard patch-clamp techniques. RESULTS: When cells were held at -70 mV and depolarized from -60 mV to +40 mV in 10 mV increments, sustained outward potassium currents were evoked. The response of medial vestibular nuclear neurons to 5-HT was not uniform. The outward potassium currents were increased in 17 of 40 cells and decreased in 23 of 40 cells. 5-carboxamidotryptamine, 5-HT1 agonist increased the outward potassium currents of the medial vestibular nuclear cell. alpha-methyl-5-hydroxytryptamine, 5-HT2 agonist decreased the outward potassium currents of the medial vestibular nuclear cell. CONCLUSION: These results suggest that 5-HT affects the potassium currents of the cell with different effects according to the receptor subtype on which it acts.
