Effects of Cyclic Nucleotide-Gated Channels in Vestibular Nuclear Neurons
10.4068/cmj.2011.47.3.155
- Author:
Tag HEO
1
;
Sujeong JANG
;
Han Seong JEONG
;
Jong Seong PARK
Author Information
1. Department of Physiology, Chonnam National University Medical School, Gwangju, Korea. Parkjs@chonnam.ac.kr
- Publication Type:Original Article
- Keywords:
Nucleotides, Cyclic;
Vestibule;
Neurons
- MeSH:
Action Potentials;
Aged;
Anesthesia;
Animals;
Ether, Ethyl;
Humans;
Neurons;
Nucleotides, Cyclic;
Patch-Clamp Techniques;
Potassium;
Pronase;
Rats;
Rats, Sprague-Dawley;
Tetraethylammonium;
Thermolysin
- From:Chonnam Medical Journal
2011;47(3):155-159
- CountryRepublic of Korea
- Language:English
-
Abstract:
This study was designed to investigate the effects an 8-Br-cGMP on the neuronal activity of rat vestibular nuclear cells. Sprague-Dawley rats aged 14 to 16 days were decapitated under ether anesthesia. After treatment with pronase and thermolysin, the dissociated vestibular nuclear cells were transferred into a chamber on an inverted microscope. Spontaneous action potentials and potassium currents were recorded by standard patch-clamp techniques under current and voltage-clamp modes. Twelve vestibular nuclear cells revealed excitatory responses to 1-5 microM of 8-Br-cGMP, and 3 neurons did not respond to 8-Br-cGMP. Whole potassium currents of vestibular nuclear cells were decreased by 8-Br-cGMP (n=12). After calcium-dependent potassium currents were blocked by tetraethylammonium, the potassium currents were not decreased by 8-Br-cGMP. These experimental results suggest that 8-Br-cGMP changes the neuronal activity of vestibular nuclear cells by blocking the calcium-dependent potassium currents that underlie the afterhyperpolarization.