Effect of local injection of botulinum toxin on sphincter of Oddi cyclic motility in dogs

Effect of acupuncture at Foot-Yangming Meridian on gastric mucosal blood flow, gastric motility and brain-gut peptide

AIM: To observe the effect of acupuncture at Foot-Yangming Meridian on gastric mucosal blood flow (GMBF), gastric motility and brain-gut peptide.

METHODS: Sixty SD rats were randomly divided into 6 groups: normal control group, model group (group with gastric mucosal damage, GMD), Sibai group (with acupuncture at Sibai point + GMD), Tianshu group (with acupuncture at Tianshu point + GMD), Zusanli group (with acupuncture at Zusanli point + GMD) and non-acupoint group (with acupuncture at non-acupoint + GMD). The GMD model group was induced by infusing pure alcohol into gastric cavity. H₂ Gas Clearance Test (HGCT) was used to measure GMBF, the frequency and amplitude of gastric motility were measured by the method of aerocyst, the content of brain-gut peptide in sinus ventriculi and bulbus medullae were detected by radioimmunoassay.

RESULTS: Inhibitory effect of the frequency and amplitude of gastric motility were shown in model group, and the rates of frequency and amplitude changes were remarkably different from the normal control group (-19.41 ± 17.21 vs -4.71 ± 10.32, P < 0.05; -51.61 ± 29.02 vs 1.81 ± 14.12, P < 0.01). In comparison with control group, the GMBF was 0.52 ± 0.161 mL vs 1.03 ± 0.255 mL per 100g tissue/min, P < 0.01, the content of motilin in sinus ventriculi and bulbus medullae was 63.04 ± 7.77 pg/mL vs 72.91 ± 8.42 pg/mL, P < 0.05 and 50.96 ± 8.77 pg/mL vs 60.76 ± 8.05 pg/mL, P < 0.05, but the content of somatostatin in sinus ventriculi and bulbus medullae was 179.85 ± 43.13 ng/g vs 90.54 ± 40.42 ng/g, P < 0.01 and 532.86 ± 122.58 ng/g vs 370.91 ± 76.29 ng/g, P < 0.05,respectively. In comparison with model group, the amplitude of gastric motility was 1.52 ± 20.13, -6.52 ± 23.31, 6.92 ± 25.21 vs -51.61 ± 29.02, P < 0.01 and GMBF was 0.694 ± 0.160 mL vs 0.893 ± 0.210 mL, 1.038 ± 0.301 mL vs 0.52 ± 0.161 mL per 100g tissue/min, P < 0.01, respectively in Tianshu, Sibai and Zusanli groups, the content of motilin in sinus ventriculi and bulbus medullae was 71.64 ± 9.35 pg/mL vs 63.04 ± 7.77 pg/mL, P < 0.05; 58.96 ± 6.69 pg/mL vs 50.96 ± 8.77 pg/mL, P < 0.05 in Zusanli group and 72.84 ± 8.62 pg/mL vs 63.04 ± 7.77 pg/mL, P < 0.05 in Sibai group, while the content of somatostatin in bulbus medullae in Tianshu, Sibai and Zusanli groups was 480.62 ± 151.69 ng/g, 388.53 ± 155.04 ng/g, 365.76 ± 143.93 ng/g vs 532.86 ± 122.58 ng/g, P < 0.05, respectively.

CONCLUSION: Electro-acupuncture at acupoints of Foot-Yangming Meridian could enhance the gastric motility, improve GMBF, and regulate the content of motilin and somatostatin in sinus ventriculi and bulbus. The effects of acupuncture on GMBF and gastric motility may be related to the content of brain-gut peptide.

Effects of electroacupuncturing at Zuyangming and Zushaoyang Jingxue on stomach and gallbladder kineses and related brain-gut peptide in rabbits

AIM: To investigate the correlation between the meridians and zang-fu as well as the specific effect of the points on their related zang-fu.

METHODS: Atropine was intravenously injected in the rabbits to inhibit the myoelectric activities of the stomach and the sphincter of oddi (SO). After electroacupuncturing at Zusanli and Yanglingquan points, the myoelectric activities of the stomach and SO were observed, and the levels of motilin (MTL) and cholcystokinin (CCK) in the antrum, SO and plasma were measured.

RESULTS: After atropine injection, the mean amplitudes for the high activity of myoelectric slow wave and fast wave were significantly decreased (P = 0.028, P = 0.001). Moreover, the average frequency of myoelectric slow wave was not significantly changed. The mean amplitudes for the myoelectric slow wave and fast wave were enhanced to some extent after electroacupuncturing at Zusanli and Yanglingquan points. The levels of MTL (P = 0.000) and CCK (P = 0.001) in the antrum, SO and plasma were increased markedly after electroacupuncturing at Zusanli and Yanglingquan points. The levels of MTL in the antrum (P = 0.020) and plasma (P = 0.001) and CCK in plasma (P = 0.001) were obviously increased after electroacupuncturing at Zusanli point, whereas the levels of MTL in SO and CCK in the antrum and SO were notably increased after electroacupuncturing at Yanglingquan point. There was a positive effect on the release of MTL and CCK after electroacupuncturing at the points.

CONCLUSION: The inhibition for the myoelectric activities of the stomach and SO are improved after electroacupuncturing at Zusanli and Yanglingquan points. The possible mechanism may be that the acupuncture influences the release of MTL and CCK, so as to regulate the activity of the alimentary canal.

The sphincter of Oddi: understanding its control and function

The most common functional disorders of the biliary tract and pancreas are associated with disordered motility of the sphincter of Oddi (SO). The SO is a neuromuscular structure located at the junction of the bile and pancreatic ducts with the duodenum. The primary functions of the SO are to regulate the delivery of bile and pancreatic juice into the duodenum, and to prevent the reflux of duodenal contents into the biliary and pancreatic systems. Disordered motility of the SO leads to the common and painful clinical conditions of SO dysfunction and acute pancreatitis. In order to understand normal SO motility, studies have been performed addressing SO function, control of spontaneous SO activity, responses to bioactive agents, SO innervation, and reflexes with other gastrointestinal organs. These studies have led to the current understanding of how the SO functions and may permit the development of targeted therapy for SO dysfunction and acute pancreatitis. This review summarizes the current knowledge regarding the control and regulation of SO motility, highlighting laboratory based and clinical research performed over the last 5 years.

Sphincter of Oddi dysfunction and other functional biliary disorders: evaluation and treatment

Functional biliary disorders encompass the conditions of SOD and gallbladder dysmotility, both of which result in clinical pain syndromes. Obtaining objective diagnostic and outcomes data for both disorders has been an ongoing challenge over the last two decades. SOD, although initially believed to be strictly a biliary disorder, has now been implicated in recurrent pancreatitis. The biliary-type classification allows a clinician to stratify patients who would benefit from SOM and endoscopic sphincterotomy. Further study into the impact of endoscopic therapy for recurrent pancreatitis is needed. By the same token, the dilemma of postcholecystectomy abdominal pain, whether classified as biliary or pancreatic type III, remains challenging. The current limitations of knowledge highlight the need for prospective randomized studies to evaluate the clinical significance of SOM abnormalities to facilitate treatment of these patients.

Effect of truncal vagotomy on sphincter of oddi cyclic motility in conscious dogs

OBJECTIVE

To evaluate the effects of truncal vagotomy at the diaphragmatic level on the sphincter of Oddi (SO) motility.

SUMMARY BACKGROUND DATA

Cholelithiasis is a well-known late complication after gastrectomy and/or vagotomy. The mechanism of gallstone formation is only partly understood, and few studies address the effects of vagotomy on SO cyclic motility in conscious subjects.

METHODS

In conscious dogs, SO motility was recorded by retrograde infusion manometry through a duodenal cannula before and after bilateral truncal vagotomy at the diaphragmatic level. Effects of cholecystokinin-octapeptide and feeding were also evaluated before and after vagotomy.

RESULTS

SO cyclic motility and the gastroduodenal migrating motor complex continued to occur during postvagotomy fasting. Intermittent inhibitions of the SO and duodenal contractions disappeared during phase 3 of the migrating motor complex. SO basal pressure significantly decreased, whereas the amplitude significantly increased. Cholecystokinin-octapeptide inhibited SO contractions before and after vagotomy. The amplitude of SO contractions increased and their frequency decreased after feeding; however, these effects disappeared after vagotomy.

CONCLUSIONS

SO cyclic motility and the effects of feeding change after truncal vagotomy at the diaphragmatic level. These facts may at least partly explain gallstone formation after gastric surgery and/or vagotomy.

Sphincter of Oddi dysfunction: is there a role for medical therapy?

If the mechanism of pain in patients with sphincter of Oddi (SO) dysfunction is functional obstruction of the biliary tract, and at least in some patients it results from sphincter smooth muscle hypertrophy, then smooth muscle relaxants should have a theoretic role in the management of these patients. Calcium channel antagonists and other smooth muscle relaxants have been shown in "acute" manometric studies to alter SO motility. However, the effect of these agents on vascular smooth muscle remains a concern and often limits their use. At present the role of medical therapy is somewhat unclear because few well-conducted studies have used manometric criteria for the diagnosis of SO dysfunction and the selection of patients for therapy. The main drawback is that no drugs appear to be specific for the SO, long acting, and free of side effects.

A comparison of common bile duct pressures after botulinum toxin injection into the sphincter of Oddi versus biliary stenting in a canine model

BACKGROUND

Botulinum toxin A (Botox) functionally paralyzes the sphincter of Oddi in both animals and humans, resulting in reduced pressures. No study, however, has specifically addressed common bile duct (CBD) pressures after Botox injection into the sphincter of Oddi with regard to treating biliary leaks and fistulae. The goals of this present study are to compare, versus biliary stenting, the change in CBD pressures after Botox injection into the sphincter of Oddi, as well as to evaluate the timing of onset and duration of these effects on sphincteric relaxation.

METHODS

After midline laparotomy in 20 mongrel dogs, a pediatric umbilical catheter was inserted into the CBD via a small cholecystotomy and attached to a water-perfused pressure transducer. After baseline CBD pressure readings, a lateral duodenotomy was performed. A total of 100 units of Botox was injected with an endoscopic sclerotherapy needle into all four quadrants of the ampulla. The dogs were randomly divided into four groups to undergo repeat laparotomy at either postoperative day 1 (group I), postoperative day 3 (group II), postoperative day 7 (group III), or postoperative day 14 (group IV). At the time of second laparotomy, a pressure-sensing catheter was reinserted into the CBD and pressures recorded. Each dog then underwent transpapillary biliary stenting with a 7 Fr. x 5 cm Cotton-Leung biliary stent and CBD pressures were again recorded.

RESULTS

CBD pressures were significantly lower as compared with baseline for all groups after Botox injection and after biliary stenting (P <0.001) In addition, no significant differences in the degree of CBD pressure reduction were identified between groups I through IV after Botox injection. The measured decrease in CBD pressure from baseline after Botox injection as compared with biliary stenting was significantly different for groups I and II (P <0.05) but not for groups III and IV.

CONCLUSION

Botox injection into the sphincter of Oddi results in significant CBD pressure reduction within 24 hours and continues for 14 days. Also, after postoperative day 3, there is no significant difference in the reduction of CBD pressure from baseline between Botox injection and biliary stenting. Based on these findings, Botox injection into the sphincter of Oddi may be a beneficial alternative to biliary stenting for the treatment of biliary leaks and fistulae.

Clinical aspects of sphincter of Oddi function and dysfunction

The sphincter of Oddi (SO) functions to regulate the flow of bile and pancreatic juices as well as to prevent the reflux of duodenal contents into the pancreatobiliary system. When dysfunction of the sphincter occurs, symptoms develop relating to either the biliary or pancreatic portions of the sphincter. The mechanism of this dysfunction remains speculative. SO manometry remains the "gold standard" to correctly diagnose the disorder and stratify therapy. Division of the sphincter is effective for SO stenosis, but there is no proven therapy for SO dyskinesia.