Ionic currents underlying HTRP3 mediated agonist-dependent Ca2+ influx in stably transfected HEK293 cells.
hTrp3 is a human homologue of the Drosophila gene responsible for a transient receptor potential (trp) mutation. When stably expressed in HEK293 cells, hTrp3 formed ion channels that were active under resting conditions but could be further stimulated by carbachol or ATP via endogenous muscarinic or purinergic receptors, respectively. Agonist evoked currents reversed polarity near 0 mV in physiological ionic conditions and were associated with a significant increase in the current variance. These results suggest the involvement of a non-selective cation channel with relatively large unitary amplitude. Consistent with this, resolved unitary events had a conductance of approximately 60 pS in the negative voltage range and an extrapolated reversal potential near 0 mV.
Hurst
R S
RS
Department of Anesthesiology, University of California, Los Angeles, 90095-1778, USA. rhurst@mednet.ucla.edu
Zhu
X
X
Boulay
G
G
Birnbaumer
L
L
Stefani
E
E
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002120:Calcium Channel Agonists / Q000494:pharmacology; D015220:Calcium Channels / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D002217:Carbachol / Q000494:pharmacology; D002460:Cell Line; D004330:Drosophila; D019204:GTP-Binding Proteins / Q000378:metabolism; D006801:Humans; D007473:Ion Channels / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D050052:TRPC Cation Channels; D014162:Transfection
D002120:Calcium Channel Agonists; D015220:Calcium Channels; D007473:Ion Channels; D050052:TRPC Cation Channels; C104603:TRPC3 cation channel; C096351:transient receptor potential cation channel, subfamily C, member 1; D000255:Adenosine Triphosphate; D002217:Carbachol; D019204:GTP-Binding Proteins; D002118:Calcium