title: Modulation of BK channel activities by calcium-sensing receptor in rat bronchopulmonary sensory neurons.
abstract: This study was carried out to investigate the expression of large-conductance Ca(2+)-activated potassium (BK) channels and to explore the possible modulation of BK channel activities by calcium-sensing receptors (CaSR) in rat bronchopulmonary sensory neurons. The expression of BK channels was demonstrated by immunohistochemistry and RT-PCR. Results from whole-cell patch-clamp recordings demonstrated that activation of CaSR with its agonist spermine or NPS R-568 showed a dual regulating effect on BK channel activities: it potentiated BK currents in cells exhibiting low baseline BK activity while slightly inhibited BK currents in cells with high baseline BK activity. Blocking CaSR with its antagonist NPS 2143 significantly inhibited BK currents. Our results further showed that the modulation of BK currents by CaSR activation or blockade was completely abolished when the intracellular Ca(2+) was chelated by BAPTA-AM. In summary, our data suggest that CaSR plays an integrative role in bronchopulmonary afferent signaling, at least partially through the regulation of BK channel activities.
authors.affiliation: Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, GA 31207, USA.
authors.forename: Zhanna V
authors.initials: ZV
authors.lastname: Vysotskaya
authors.affiliation: Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, GA 31207, USA.
authors.forename: Charles R
authors.initials: CR
authors.lastname: Moss
authors.affiliation: Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, GA 31207, USA.
authors.forename: Carolyn A
authors.initials: CA
authors.lastname: Gilbert
authors.affiliation: Department of Family Medicine, Mercer University School of Medicine and Medical Center of Central Georgia, Macon, GA 31207, USA.
authors.forename: Sabry A
authors.initials: SA
authors.lastname: Gabriel
authors.affiliation: Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, GA 31207, USA. Electronic address: GU_Q@mercer.edu.
authors.forename: Qihai
authors.initials: Q
authors.lastname: Gu
mesh_terms: D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D055592:Biophysical Phenomena / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D002232:Carbocyanines / Q000378:metabolism; D002614:Chelating Agents / Q000494:pharmacology; D004533:Egtazic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D004558:Electric Stimulation; D017950:Ganglia, Sensory / Q000166:cytology; D005924:Glomus Jugulare / Q000166:cytology; D051036:Large-Conductance Calcium-Activated Potassium Channels / Q000235:genetics / Q000378:metabolism*; D009281:Naphthalenes / Q000494:pharmacology; D018408:Patch-Clamp Techniques; D026902:Potassium Channel Blockers / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D044169:Receptors, Calcium-Sensing / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D011984:Sensory Receptor Cells / Q000187:drug effects / Q000502:physiology*; D050916:TRPV Cation Channels / Q000235:genetics / Q000378:metabolism
chemical_list: D002232:Carbocyanines; D002614:Chelating Agents; D051036:Large-Conductance Calcium-Activated Potassium Channels; C436740:N-(2-hydroxy-3-(2-cyano-3-chlorophenoxy)propyl)-1,1-dimethyl-2-(2-nephthyl)ethylamine; D009281:Naphthalenes; D026902:Potassium Channel Blockers; D044169:Receptors, Calcium-Sensing; D050916:TRPV Cation Channels; C493922:Trpv1 protein, rat; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; C024286:3,3'-dioctadecylindocarbocyanine; D004533:Egtazic Acid; D002118:Calcium
keywords: Bronchopulmonary sensory neuron; Calcium-sensing receptor; Large-conductance Ca(2+)-activated potassium channel; Transient receptor potential vanilloid receptor 1