Pentobarbital: action on frog motoneurons
Pentobarbital: action on frog motoneurons
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戊巴比妥：对青蛙运动神经元的作用
DOI：
10.1016/0006-8993(75)90582-x
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发表时间：
1975
期刊：
影响因子：
2.9
通讯作者：
R. Nicoll
中科院分区：
文献类型：
--
作者：
R. Nicoll
图1.戊巴比妥对青蛙运动神经元的超极化作用。答：GABA和戊巴比妥(BARB)引起超极化，而DNP引起去极化。B区GABA和戊巴比妥钠反应可被印防己毒素(2×10~4M)可逆地拮抗。GABA浓度为5×10~(-4)M，戊巴比妥钠浓度为4×10~(-4)M，DNP浓度为5~10~(-4)M，阳性率为5~10~(-4)M，向下为超极化。以往研究表明，麻醉剂可增加膜对钾离子的电导，从而使一些无脊椎动物神经元S、23、30产生超极化。由于二硝基苯酚(DNP)也增加某些神经元的钾电导，1~，18有人提出麻醉剂24对代谢的抑制可能是这些膜效应的基础。然而，在青蛙运动神经元上，DNP(-gt；0.5 mM)总是使膜去极化(图1a)，这表明干扰细胞代谢不是本研究中看到的超极化的基础。
Fig. 1. Hyperpolarizing action of pentobarbital on frog motoneurons. A: GABA and pentobarbital (BARB) elicit a hyperpolarization while DNP elicits a depolarization. In B the GABA and pentobarbital responses are reversibly antagonized by picrotoxin (2× 10~ 4 M). The concentration of GABA was 5× 10 4M, pentobarbital was 4× 10-a M, and DNP was 5~" 10-4 M. Positivity in this and the following figure is downward signifying a hyperpolarization.Previous studies have shown that anesthetics can increase membrane conductance to potassium ions, thus producing a hyperpolarization of some invertebrate neuronsS, 23, 30. Since dinitrophenol (DNP) also increases the potassium conductance of some neurons, it has been proposed 1~, 18 that the inhibition of metabolism by anesthetics 24 might be the basis for these membrane effects. However, on frog motoneurons DNP (> 0.5 mM) invariably depolarized the membrane (Fig. 1A), suggesting that interference with cellular metabolism is not the basis for the hyperpolarization seen in the present study.