Basic rhythm of myoelectric activities of sphcter of Oddi and its biological significance / 中华肝胆外科杂志

ABSTRACT

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.