BLOCK BY THE NEUROPEPTIDE TRH OF AN APPARENTLY NOVEL K+ CONDUCTANCE OF RAT MOTONEURONS

被引：22

作者：

NISTRI, A ^{[1
]}

FISHER, ND ^{[1
]}

GURNELL, M ^{[1
]}

机构：

[1] UNIV LONDON ST BARTHOLOMEWS HOSP,DEPT PHARMACOL,LONDON EC1M 6BQ,ENGLAND

来源：

NEUROSCIENCE LETTERS | 1990年 / 120卷 / 01期

关键词：

Barium; Motoneuron; Potassium conductance; Spinal cord; TRH;

D O I：

10.1016/0304-3940(90)90159-7

中图分类号：

Q189 [神经科学];

学科分类号：

071006 ;

摘要：

Using a single electrode voltage clamp technique the actions of rapidly superfused thyrotropin-releasing hormone (TRH, 1 μM) on lumbar motoneurones of the isolated neonatal rat spinal cord were investigated. TRH induced a slowly developing inward current (associated with an input conductance fall) with slow recovery on washout. In the presence of TRH the normally linear current-voltage relations displayed strong inward rectification up to about -40 mV. The TRH-induced current peaked at -50 mV, reversed at -120 mV and was not blocked by Cs+, tetraethylammonium, 4-aminopyridine, Cd2+, or low Na+. Its reversal potential was sensitive to changes in extracellular K+. Ba2+ (0.2-1.5 mM) depressed the effects of TRH. It is suggested that in rat motoneurones TRH blocked an apparently novel K+ conductance (IK(T)) active at resting membrane potential. © 1990.

引用

页码：25 / 30

页数：6

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