Oddi括约肌肌电活动的基本方式

目的 探讨家兔Oddi括约肌(sphincter of Oddi,SO)肌电活动的基本方式及其生物学意义.方法 32只家兔随机分为4组.第1组(n=8)为空腹组;第2组(n=8)为进食组,空腹18 h后经胃造瘘管注入50 ml牛奶;第3组(n=8)为Nardi test激发实验组,静脉注射1 mg吗啡和1 mg新斯的明;第4组(n=8)为神经阻断组,记录空腹家兔肌电活动30 min后静脉给予山莨菪硷1 mg;两对钩状双极金属电极通过浆膜层分别置于SO及十二指肠,使用RM6240多道生理信号采集处理系统同时记录每一组家兔SO及十二指肠肌电活动,连续记录SO肌电活动120～150 min.结果 空腹状态下家兔SO肌电表现为规律的、单发性的SPSO;进食后家兔SO肌电活动表现为规律的、间断的MASO;Nardi test激发实验后SO肌电活动表现为数个长时间、不间断的SPSO组成的肌电串;阻断神经节后胆碱能神经元后SO肌电活动规律随即消失,120 min后SPSO逐渐恢复到空腹状态.结论 家兔SO肌电活动存在4种基本形式,即空腹状态下SO保持一定基础紧张性的基本张力波;进食后SO开始蠕动将胆汁排入十二指肠的蠕动波;Nardi test激发实验后SO处于持续关闭状态的痉挛波;阻断胆碱能神经元后SO处于松弛状态的舒张波.提示SO并非仅仅存在"非开即闭"两种形式.这对今后有关SO基础研究和临床治疗均具有理论指导意义.

Basic rhythm of myoelectric activities of sphcter of Oddi and its biological significance

Objective To observe the basic rhythm of myoelectrie activities of sphcter of Oddi (SO)and explore its biological significance.Methods Healthy adult rabbits(n=32)were randomized into 4 groups with 8 in each.The first group was for recording of myoelectric activities of SO after keeping fast for 18 hours.The second group was manipulated to observe the myoelectric activities of SO after food infusion through the stoma in stomach.The myoelectric activities of SO in the third group were monitored after the classical Nardi test was performed on these rabbits.The fourth group was used to observe the myoelectric activities of SO after the cholinergic receptors had been blocked.Using the double claw metal electrodes which were put into SO and duodenum through the plasma membrance,the myoelectric signal were recorded with RM6240 multi-channel physiologic recording and signal processing system and non-stop recording was conducted for 120-150 mins.Results 1)Spike Potentials of SO with the frequency was observed in rabbits that had been fasting.2)Myoelectronic activity of SO was observed in rabbits infused with 50 ml milk through stoma.3)After the administration of 1 mg morphine and 1 mg neostigmine i.v,the myoelectric activities of SO were noted as long-lasting persistent MASO.4)Administration of anisodamine 1 mg(i.v.)in the empty abdomen group dismissed SPSO and MASO.This state lasted for 120 min before SPSO gradually reconverted to the state of empty abdomen.Conclusion There are four patterns of myoelectric activities of SO,i.e,tensional waves under empty abdomen indicating a state in which the SO kept a basic tension level.Peristaltic waves under intake of food.Spastic waves under the stimulation of drugs and relaxant waves under the post-ganglionic block of cholinergic receptors were observed in the present study.Correspondingly,their mechanic locomotion is inferred as the basic tensional state to faciliate the deposition and condensation of bile,the peristalsis for the entry of bile into duodenum,the spasmus so that the bile can not be released into duodenum under pathological situation or the effect of drugs.the long lasting relaxant state after effective inhibition of post-ganglionic cholinergic receptors,respectively.The above results indicate that there are more than two states that is ON or OFF in SO and the concepts of contract and peristalsis of SO should be distinguished.