Department of Oral Physiology and BK21 program, School of Dentistry and Institute of Oral Bioscience, Chonbuk National University, Jeonju, 561-756, Republic of Korea.
Phytother Res. 2010 Aug;24(8):1147-50. doi: 10.1002/ptr.3088.
The effect of the methanol extract of Withania somnifera (mWS) on the gonadotropin releasing hormone (GnRH) neuron was examined in juvenile mice using the whole cell patch clamp technique. GnRH neurons are the fundamental regulators of the pulsatile release of GnRH needed for puberty and fertility. GnRH neurons were depolarized by bath application of the mWS (400 ng/microl) under the condition of a high Cl(-) pipette solution in current clamp mode. In voltage clamp mode, mWS induced reproducible inward currents (31.7 +/- 5.51 pA, n = 14). The mWS-induced inward currents persisted in the presence of tetrodotoxin (TTX, 0.5 microM), but were suppressed by bicuculline methiodide (BMI, 20 microM), a GABA(A) receptor antagonist. These results show that mWS affects the neuronal activities by mediating the GABA(A) receptor, which suggests that WS contains an ingredient with possible GABAmimetic activity.
采用全细胞膜片钳技术，在未成年小鼠中研究了睡茄甲醇提取物（mWS）对促性腺激素释放激素（GnRH）神经元的影响。GnRH 神经元是青春期和生育期所需 GnRH 脉冲释放的基本调节者。在电流钳模式下，用高 Cl(-) 管内溶液对浴液施加 mWS（400ng/微升），使 GnRH 神经元去极化。在电压钳模式下，mWS 诱导可重现的内向电流（31.7 +/- 5.51pA，n=14）。mWS 诱导的内向电流在河豚毒素（TTX，0.5μM）存在的情况下持续存在，但被 GABA(A) 受体拮抗剂印防己毒素（BMI，20μM）抑制。这些结果表明，mWS 通过介导 GABA(A) 受体影响神经元活动，这表明 WS 含有具有 GABA 类似活性的成分。
