Inhibitory effect of memantine, an NMDA-receptor antagonist, on electoporation-induced inward currents in pituitary GH3 cells

Sheng Nan Wu, Hsien Ching Huang, Chia Chen Yeh, Wei Hsin Yang, Yi Ching Lo

研究成果: Article同行評審

12 引文 斯高帕斯(Scopus)

摘要

The membrane electroporation-induced inward current (IMEP) in pituitary tumor (GH3) cells was characterized. This current emerges irregularly when membrane hyperpolarizations to -200mV with a holding potential of -80mV were elicited. Neither E-4031 (10μM), glibenclamide (30μM), nor ZD7288 (30μM) caused any effects on IMEP. The single-channel conductance and pore radius were estimated to be around 1.12nS and 1.7nm, respectively. LaCl3- and memantidine (MEM)-induced block of this current was also examined. The IC50 value for LaCl3- and MEM-induced inhibition of IMEP was 35 and 75μM, respectively. However, unlike LaCl3, MEM (300μM) did not exert any effect on voltage-gated Ca2+ current. In inside-out configuration, MEM applied to either external or internal surface of the excised patch did not suppress the activity of ATP-sensitive K+ channels expressed in GH3 cells, although glibenclamide significantly suppressed channel activity. This study provides the first evidence to show that MEM, a non-competitive antagonist of N-methyl D-aspartate receptors, directly inhibits the amplitude of IMEP in pituitary GH3 cells. MEM-mediated block of IMEP in these cells is unlinked to its inhibition of glutamate-induced currents or ATP-sensitive K+ currents. The channel-suppressing properties of MEM might contribute to the underlying mechanisms by which it and its structurally related compounds affect neuronal or neuroendocrine function.

原文English
頁(從 - 到)508-513
頁數6
期刊Biochemical and Biophysical Research Communications
405
發行號3
DOIs
出版狀態Published - 2011 2月 18

All Science Journal Classification (ASJC) codes

  • 生物物理學
  • 生物化學
  • 分子生物學
  • 細胞生物學

指紋

深入研究「Inhibitory effect of memantine, an NMDA-receptor antagonist, on electoporation-induced inward currents in pituitary GH3 cells」主題。共同形成了獨特的指紋。

引用此