Dual effects of pentobarbital on rat sacral dorsal commissural neurons in vitro
Pang, Z.P.; Xu, T.L.; Hu, G.Y.; Li, J.S.
Zhongguo Yao Li Xue Bao 19(4): 327-331
1998
ISSN/ISBN: 0253-9756 PMID: 10375777 Document Number: 486406
To study the effects of pentobarbital (PB) on acutely dissociated rat sacral dorsal commissural neurons (SDCN). Nystatin-perforated patch clamp recording was used. (1) At a holding potential of -40 mV, PB induced inward Cl- current (IPB) in a concentration-dependent manner with a EC50 (95% confidence limits) of 416 (385-477) mumol.L-1 and a Hill coefficient of 1.08. (2) Picrotoxin reversibly blocked IPB. (3) The reversal potential of IPB was close to the Cl- equilibrium potential. (4) PB enhanced GABA-induced Cl- influx (IGABA). In the presence of PB 30 mumol.L-1, the EC50 (95% confidence limits) of IGABA decreased from 6.9 (5.4-8.4) mumol.L-1 to 3.5 (2.9-4.1) mumol.L-1. PB had dual effects on SDCN, facilitated GABAA receptor-mediated currents and at higher concentrations induced Cl- influx itself.