Toosendanin increases free-Ca(2+) concentration in NG108-15 cells via L-type Ca(2+) channels.
OBJECTIVE
To examine if toosendanin (TSN) affects intracellular free-Ca(2+) concentration ([Ca(2+)](i)) in neuroblastoma pluglioma hybrid cells (NG108-15 cells).


METHODS
The [Ca(2+)](i) was determined by laser-scanning confocal microscopic imaging technique in which Fluo-3 was used as Ca(2+) indicator.


RESULTS
TSN induced an increase in resting [Ca(2+)](i) and in high K(+)-evoked Ca(2+) transient in differentiated NG108-15 cells. The TSN-induced increase in [Ca(2+)](i) was dose-dependent and disappeared in CdCl(2-), nifedipine-containing or Ca(2+)-free solution, and appeared after washing out the Ca(2+) channel blockers or adding Ca(2+).


CONCLUSIONS
TSN increased [Ca(2+)](i) in differentiated NG108-15 cells. The [Ca(2+)](i) enhancement was due to the influx of extracellular Ca(2+) and related to L-type Ca(2+) channels.
Xu
Tong-hui
TH
Key Laboratory of Neurobiology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
Ding
Jun
J
Shi
Yu-liang
YL
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D020746:Calcium Channels, L-Type / Q000502:physiology*; D020747:Calcium Channels, T-Type / Q000502:physiology; D002454:Cell Differentiation / Q000502:physiology; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D005910:Glioma / Q000473:pathology; D006822:Hybrid Cells; D009447:Neuroblastoma / Q000473:pathology; D009543:Nifedipine / Q000494:pharmacology; D014407:Tumor Cells, Cultured; D014315:Triterpenes
D002118:Calcium; D002121:Calcium Channel Blockers; D020746:Calcium Channels, L-Type; D020747:Calcium Channels, T-Type; D004365:Drugs, Chinese Herbal; D009543:Nifedipine; C036454:toosendanin; D014315:Triterpenes