Blaustein M P
J Pharmacol Exp Ther. 1976 Jan;196(1):80-6.
The effects of two barbiturates on calcium uptake by sympathetic ganglia have been examined. Sodium pentobarbital (0.4-0.75 mM) and sodium thiopental (0.3 mM) block the preganglionic stimulation-induced uptake of 45Ca by rat superior cervical ganglia but not action potential conduction in the presynaptic axons. The ganglionic-blocking agent, tetraethylammonium, does not inhibit stimulation-induced Ca uptake and does not prevent the blocking effect of thiopental. This effect is therefore probably presynaptic. Postassium-rich media also stimulate Ca uptake by the ganglia, and this effect is markedly inhibited by pentobarbital. Since the K stimulation effect is also observed in deafferented ganglia but not in guanethidine-denervated ganglia, this effect is probably associated primarily with postsynaptic elements. In sum, the data suggest that the barbiturates inhibit Ca permeability changes in both pre- and postsynaptic neurons.
研究了两种巴比妥类药物对交感神经节摄取钙的影响。戊巴比妥钠（0.4 - 0.75 mM）和硫喷妥钠（0.3 mM）可阻断节前刺激诱导的大鼠颈上神经节对45Ca的摄取，但不影响突触前轴突的动作电位传导。神经节阻断剂四乙铵不抑制刺激诱导的钙摄取，也不能阻止硫喷妥钠的阻断作用。因此，这种作用可能是突触前的。富含钾的培养基也能刺激神经节摄取钙，而这种作用被戊巴比妥显著抑制。由于在去传入神经节中也观察到钾刺激作用，但在胍乙啶去神经节中未观察到，这种作用可能主要与突触后成分有关。总之，数据表明巴比妥类药物抑制突触前和突触后神经元的钙通透性变化。
