BLADDER CONTRACTION INDUCED BY TETRAETHYLAMMONIUM IONS

DOI Web Site
  • Tsuda Hiroshi
    Department of Physiology, School of Medicine, Showa University

Bibliographic Information

Other Title
  • Tetraethylammoniumイオンによって誘起される膀胱筋の収縮
  • Tetraethylammonium イオン ニ ヨッテ ユウキサレル ボウコ

Search this article

Description

It was reported that tetraethylammonium (TEA) ion caused twitch in skeltal muscle and its mechanism was explained by the enhancement of transmitter release from nerve endings due to TEA action on it.<BR>Whether such TEA action is observed in nerve terminals of smooth muscle was investigated by recording the inner pressure of isolated guinea pig bladder.<BR>When bladder was immersed in TEA Krebs' solution in which Na ions were replaced by TEA ions, large rapidly developing phasic, gradual declining contraction was induced.<BR>After treatment of bladder with atropine, initial phasic contraction disappeared and low amplitude sustained contraction remained, while contraction induced by acetylcholine was completely abolished by atropine.In the treatment of 10-5 g/ml tetrodotoxin, TEA contraction still remained, rather augmented. After immersion of bladder in sucrose Krebs' solution in which Na ions were replaced by sucrose, TEA contraction unchanged and atropine abolished initial phasic contraction in smillar manner as normal TEA contraction.<BR>On the other hand, when bladder was immersed in Ca free adding 1.3 mM EDTA solution or in CdCl2 containing Krebs' solution, TEA and ACh contractions disappeared almost completely. In latter, abolishment of contraction was restored by cysteine.<BR>Bladder contraction induced by direct stimulation or indirect stimulation also unchangec in Na lack medium, while these were abolished in Ca lack adding EDTA medium.<BR>These dataes indicate that 1) TEA acting on bladder liberates transmitter from nerve endings and cause contraction as observed in skeltal muscle, 2) Tetrodotoxin did not influence on transmitter releasing like in motor nerve terminal, 3) Na ions did not influenced on either bladder contraction or release of transmitter from nerve endings, while lack of Ca strongly depressed bladder contraction.

Journal

Details 詳細情報について

Report a problem

Back to top