Effects of okadaic acid on voltage-gated potassium and calcium channels in cultured rat trigeminal neurons
- VernacularTitle:冈田酸对培养的大鼠三叉神经元电压门控性钾和钙通道的调节
- Author:
Hong XIE
;
Xuehong CAO
;
Zhangyin MING
;
Xuesong CAO
;
Gang LEI
;
Fen LI
;
Changjin LIU
;
Lieju LIU
- Publication Type:Journal Article
- Keywords:
okadaic acid;
phosphoprotein phosphatase;
patch-clamp technique;
trigeminal ganglion;
neurons;
ion chnnels
- From:
Chinese Journal of Pharmacology and Toxicology
2007;21(5):369-376
- CountryChina
- Language:Chinese
-
Abstract:
AIM To investigate the effects of serine/threonine protein phosphatases in regulation of cell signal transduction on voltage-gated potassium and calcium channels in cultured rat trigeminal ganglion (TRG) neurons. METHODS Whole-cell patch clamp technique was used to record the potassium and calcium currents from adult rat TRG neurons before and after perfusion of okadaic acid, a potent inhibitor of the serine/threonine protein phosphatases 1 and 2A. RESULTS Okadaic acid 1 μmol·L-1 inhibited transient outwards potassium currents (IA) by 28.6%, increased delay rectified potassium currents (IK) and calcium currents (ICa) by 22.7% and 20.0%, respectively. okadaic acid 1 μmol·L-1 produced significant hyperpolarizing shifts in the conductance-voltage (G-V) curves and inactivation curves of IA , also produced significant hyperpolarizing shifts in the G-V curves of IK, while it had no effect on the activation and inactivation kinetics of ICa. CONCLUSION Serine/threonine protein phosphatases 1 and 2A may be involved in the modulation of voltage-gated potassium and calcium channels on rat TRG neurons. In addition, voltage-gated potassium and calcium channels show different dependence on the dephosphorylation reactions of PP1 and PP2A phosphatases.
