A novel Ca(v)2.2 channel inhibition by piracetam in peripheral and central neurons
Por:
Bravo-Martinez, J, Arenas, I, Vivas, O, Rebolledo-Antunez, S, Vazquez-Garcia, M, Larrazolo, A, Garcia, DE
Publicada:
1 oct 2012
Resumen:
No mechanistic actions for piracetam have been documented to support its nootropic effects. Voltage-gated calcium channels have been proposed as a promising pharmacological target of nootropic drugs. In this study, we investigated the effect of piracetam on Ca(v)2.2 channels in peripheral neurons, using patch-clamp recordings from cultured superior cervical ganglion neurons. In addition, we tested if Ca(v)2.2 channel inhibition could be related with the effects of piracetam on central neurons. We found that piracetam inhibited native Ca(v)2.2 channels in superior cervical ganglion neurons in a dose-dependent manner, with an IC50 of 3.4 mu mol/L and a Hill coefficient of 1.1. GDP/3S dialysis did not prevent piracetam-induced inhibition of Ca(v)2.2 channels and G-protein-coupled receptor activation by noradrenaline did not occlude the piracetam effect. Piracetam altered the biophysical characteristics of Ca(v)2.2 channel such as facilitation ratio. In hippocampal slices, piracetam and om
Filiaciones:
Bravo-Martinez, J:
Univ Nacl Autonoma Mexico, Sch Med, Dept Physiol, Mexico City 04510, DF, Mexico
Arenas, I:
Univ Nacl Autonoma Mexico, Sch Med, Dept Physiol, Mexico City 04510, DF, Mexico
Vivas, O:
Univ Nacl Autonoma Mexico, Sch Med, Dept Physiol, Mexico City 04510, DF, Mexico
Rebolledo-Antunez, S:
Univ Nacl Autonoma Mexico, Sch Med, Dept Physiol, Mexico City 04510, DF, Mexico
Vazquez-Garcia, M:
Univ Nacl Autonoma Mexico, Sch Med, Dept Physiol, Mexico City 04510, DF, Mexico
Larrazolo, A:
Univ Nacl Autonoma Mexico, Sch Med, Dept Physiol, Mexico City 04510, DF, Mexico
Garcia, DE:
Univ Nacl Autonoma Mexico, Sch Med, Dept Physiol, Mexico City 04510, DF, Mexico
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