These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: ATP-activated nonselective cation current in NG108-15 cells. Author: Kaiho H, Kimura J, Matsuoka I, Kumasaka T, Nakanishi H. Journal: J Neurochem; 1996 Jul; 67(1):398-406. PubMed ID: 8667019. Abstract: ATP (1 mM) induced a biphasic increase in intracellular Ca2+ concentration ([Ca2+]i), i.e., an initial transient increase decayed to a level of sustained increase, in NG108-15 cells. The transient increase was inhibited by a phospholipase C inhibitor, 1-[6[[17beta-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H- pyrrole-2,5-dione (U73122), whereas the sustained increase was abolished by removal of external Ca2+. We examined the mechanism of the ATP-elicited sustained [Ca2+]i increase using the fura-2 fluorescent method and the whole-cell patch clamp technique. ATP (1 mM) induced a membrane current with the reversal potential of 12.5 +/- 0.8 mV (n = 10) in Tyrode external solution. The EC50 of ATP was approximately 0.75 mM. The permeability ratio of various cations carrying this current was Na+ (defined as 1) > Li+ (0.92 +/- 0.01; n = 5) > K+ (0.89 +/- 0.03; n = 6) > Rb+ (0.55 +/- 0.02; n = 6) > Cs+ (0.51 +/- 0.01; n = 5) > Ca2+ (0.22 +/- 0.03; n = 3) > N-methyl-D-glucamine (0.13 +/- 0.01; n = 5), suggesting that ATP activated a nonselective cation current. The ATP-induced current was larger at lower concentrations of external Mg2+. ATP analogues that induced the current were 2-methylthio-ATP (2MeSATP), benzoylbenzoic-ATP, adenosine 5'-thiotriphosphate (ATPgammaS), and adenosine 5'-O-(2-thiodiphosphate), but not adenosine, ADP, alpha,beta-methylene-ATP (AMPCPP), beta,gamma-methylene-ATP (AMPPCP), or UTP. Concomitant with the current data, 2MeSATP and ATPgammaS, but not AMPCPP or AMPPCP, increased the sustained [Ca2+]i increase. We conclude that ATP activates a class of Ca2+-permeable nonselective cation channels via the P2z receptor in NG108-15 cells.[Abstract] [Full Text] [Related] [New Search]