Article: Functional expression of L-, N-, P/Q-, and R-type calcium channels in the human NT2-N cell line.
2000 Volume 84, Issue 6, Page(s) 2933–2944
Abstract: ... reduced further by SNX-482 (7-14% of current remained), consistent with functional expression of L-, N ... and P/Q-calcium channel types and one or more R-type channel. The presence of multiple calcium ... of the regulation, expression and cellular function of human derived calcium channel currents; in particular the R ...
Abstract | The biophysical and pharmacological properties of voltage-gated calcium channel currents in the human teratocarcinoma cell line NT2-N were studied using the whole cell patch-clamp technique. When held at -80 mV, barium currents (I(Ba)s) were evoked by voltage commands to above -35 mV that peaked at +5 mV. When holding potentials were reduced to -20 mV or 5 mM barium was substituted for 5 mM calcium, there was a reduction in peak currents and a right shift in the current-voltage curve. A steady-state inactivation curve for I(Ba) was fit with a Boltzmann curve (V(1/2) = -43.3 mV; slope = -17.7 mV). Maximal current amplitude increased from 1-wk (232 pA) to 9-wk (1025 pA) postdifferentiation. Whole cell I(Ba)s were partially blocked by specific channel blockers to a similar extent in 1- to 3-wk and 7- to 9-wk postdifferentiation NT2-N cells: 10 microM nifedipine (19 vs. 25%), 10 microM conotoxin GVIA (27 vs. 25%), 10 microM conotoxin MVIIC (15 vs. 16%), and 1.75 microM SNX-482 (31 vs. 33%). Currents were completely blocked by 300 microM cadmium. In the presence of nifedipine, GVIA, and MVIIC, approximately 35% of current remained, which was reduced further by SNX-482 (7-14% of current remained), consistent with functional expression of L-, N-, and P/Q-calcium channel types and one or more R-type channel. The presence of multiple calcium currents in this human neuronal-type cell line provides a potentially useful model for study of the regulation, expression and cellular function of human derived calcium channel currents; in particular the R-type current(s). |
---|---|
MeSH term(s) | Calcium Channel Blockers/pharmacology ; Calcium Channels/biosynthesis ; Calcium Channels, L-Type/biosynthesis ; Calcium Channels, N-Type/biosynthesis ; Calcium Channels, P-Type/biosynthesis ; Calcium Channels, Q-Type/biosynthesis ; Calcium Channels, R-Type/biosynthesis ; Cell Differentiation ; Dose-Response Relationship, Drug ; Humans ; Membrane Potentials/drug effects ; Neurons/cytology ; Neurons/drug effects ; Neurons/metabolism ; Nifedipine/pharmacology ; Patch-Clamp Techniques ; Spider Venoms/pharmacology ; Teratocarcinoma/metabolism ; Teratocarcinoma/pathology ; Tumor Cells, Cultured ; omega-Conotoxin GVIA/pharmacology ; omega-Conotoxins/pharmacology |
Chemical Substances | Calcium Channel Blockers ; Calcium Channels ; Calcium Channels, L-Type ; Calcium Channels, N-Type ; Calcium Channels, P-Type ; Calcium Channels, Q-Type ; Calcium Channels, R-Type ; SNX 482 ; Spider Venoms ; omega-Conotoxins ; omega-conotoxin-MVIIC (147794-23-8) ; omega-Conotoxin GVIA (92078-76-7) ; Nifedipine (I9ZF7L6G2L) |
Language | English |
Publishing date | 2000-12 |
Publishing country | United States |
Document type | Journal Article ; Research Support, U.S. Gov't, P.H.S. |
ZDB-ID | 80161-6 |
ISSN | 1522-1598 ; 0022-3077 |
ISSN (online) | 1522-1598 |
ISSN | 0022-3077 |
Database | MEDical Literature Analysis and Retrieval System OnLINE |
More links
Kategorien
In stock of ZB MED Cologne/Königswinter
Uc I Zs.224: Show issues | Location: Je nach Verfügbarkeit (siehe Angabe bei Bestand) bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular ab Jg. 2022: Lesesaal (EG) |
Order via subito
This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.