Effects of biliary tract pressure on dynamics of the Oddi's sphincter and its nerve mechanism.

Abstract

In order to explore the effect of biliary tract pressure on Oddi's sphincter and the mechanism of development of high pressure of biliary tract during acute obstructive and suppurative cholangitis (AOSC), house rabbits were used to establish model of high biliary pressure in acute biliary duct caecus. It was observed that when the pressure of the acute biliary tract was increased to 8 kPa, the electric activity of Oddi's sphincter was obviously enhanced, the pressure of Oddioes sphincter increased remarkably (P < 0.05), and even constant spasm appeared with accompanying increase of discharge frequency of the right greater splanchnic nerves (P < 0.05) and progressive decrease of mean arterial pressure. However, when lidocaine of 0.6% was used to block the right celiac plexus, no above-mentioned reaction happened when the biliary tract pressure was increased again. The results indicated that the acute biliary tract obstruction might induce the contraction or spasm of Oddi's sphincter and bring about a vicious cycle. Its mechanism is related to splanchnic nerves reflection and it is one of important factors in the development of AOSC course.