Isolation of Voltage Dependent Calcium Current in Chick Inner Hair Cell.
10.3342/kjorl-hns.2009.52.8.655
- Author:
Seung Hwan LEE
1
;
Myung Chul SHIN
;
Tae Hwan AHN
;
Ki Yong KIM
;
Kuk KIM
;
Hyun Jung MIN
;
Chul Won PARK
Author Information
1. Department of Otolaryngology-Head and Neck Surgery, College of Medicine, Hanyang University, Seoul, Korea. shleemd@hanyang.ac.kr
- Publication Type:Original Article
- Keywords:
Hair cell;
Calcium channel
- MeSH:
Apamin;
Calcium;
Calcium Channels;
Calcium Channels, L-Type;
Cesium;
Cochlea;
Egtazic Acid;
Ethylenes;
Hair;
Hair Cells, Vestibular;
Neurons, Afferent;
Neurotransmitter Agents;
Organ of Corti;
Potassium;
Synaptic Transmission;
Tetraethylammonium;
Vertebrates
- From:Korean Journal of Otolaryngology - Head and Neck Surgery
2009;52(8):655-659
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND AND OBJECTIVES: Voltage dependent calcium channel (VDCC) mediates calcium ion influx and controls neurotransmitter release in excitable cells. Hair cells in vertebrates cochlea are known to express L-type VDCC. The purpose of this study was to measure calcium current from hair cells to investigate basic activity and characteristics of VDCC. MATERIALS AND METHOD: We measured calcium current in hair cells of the chicken's auditory organ, the basilar papilla analogous to the mammalian cochlea, in whose L-type, dihydropyridinesensitive calcium channels predominate and in vestibular hair cells from cristae. Calcium currentthrough VDCC was isolated in voltage-clamp recording using Cesium, Tetraethylammonium, 4- aminopyridine and apamin to block the much larger potassium currents. Various concentrations of internal calcium buffer, ethylene glycol tetraacetic acid (EGTA) or 1,2-bis (o-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid (BAPTA) were used. RESULTS: The higher the buffer concentration, the larger the current size were ; they were significantly larger in 10 mM of calcium buffer concentration (ANOVA, p< 0.05). There was no difference in calcium current between cochlear and vestibular hair cells. CONCLUSION: We could successfully isolate stable inward calcium current from chick hair cells. This experiment can be used as a basic method to understand neurotransmission process between hair cells and afferent neurons.
