Certain aspects of normal and abnormal motility of sphincter of Oddi

Effect of cholesterol liposomes on calcium mobilization in muscle cells from the rabbit sphincter of Oddi

AIM: To analyze the influence of cholesterol liposome on the Ca²⁺ mobilization of cultured muscle cells in rabbit sphincter of Oddi’s.

METHODS: New Zealand rabbit was sacrificed and the sphincter of Oddi (SO) segement was obtained aseptically. The SO segment was cut into pieces and cultured in DMEM solution. Then the smooth muscle cells were subcultured, and the 4th-7th passage cells were used for further investigation. The intracellular Ca²⁺ increase was measured under confocal microscope after the addition of 20 mmol·L^-1 KCl, 10^-7 mol·L^-1 acetylcholine and 10^-7 mol·L^-1 cholecystokinin, and different antagonists were added to analyze the Ca²⁺ mobilization pathway. After the cells were incubated with 1 g·L^-1 cholesterol liposome (CL)(molar ratio was-2:1), the intracellular Ca²⁺ increase was measured again to determine the effect of CL on cellular Ca²⁺ mobilization.

RESULTS: The resting cellular calcium concentration of cultured SO cell was 108 nmol·L^-1± 21 nmol·L^-1. The intracellular Ca²⁺ increases induced by 20 mmol·L^-1 KCl, 10^-7 mol·L^-1 ACh and 10^-7 mol·L^-1 CCK were 183% ± 56%, 161% ± 52% and 130% ± 43%, respectively. When the extracellular Ca²⁺ was eliminated by 2 mmol·L^-1 EGTA and 5 μmol·L^-1 verapamil, the intracellular Ca²⁺ increases induced by KCl, ACh and CCK were 20% ± 14%, 82% ± 21% and 104% ± 23%, respectively. After the preincubation with heparin, the Ca²⁺ increases were 62% ± 23% and 23% ± 19% induced by ACh and CCK, as for preincubation with procaine they were 72% ± 28% and 85% ± 37% induced by ACh and CCK, respectively. Pretreatment with CL for 18 h, the resting cellular Ca²⁺ concentration elevated to 152 nmol·L^-1± 26 nmol·L^-1, however, the cellular Ca²⁺ increase percentages in response to these agonists were 67% ± 32%, 56% ± 33% and 34% ± 15%.

CONCLUSION: KCl elicite the SO cellular Ca²⁺ increase depends on influx of extracellular Ca²⁺, ACh evoked the SO celllular Ca²⁺ increase is through the mobilization of intracellular Ca²⁺ pool and influx of extracellular Ca²⁺ as well, CCK excites the SO cells mainly through mobilization of intracellular IP3-sensitive Ca²⁺ store. After the incorporation with cholesterol liposome, KCl,ACh and CCK induced cellular Ca²⁺ increase percentages decreased.

Effects of trimebutine on sphincter of Oddi motility in patients with post-cholecystectomy pain

BACKGROUND

Trimebutine is an opiate modulator of the gastrointestinal motility that interacts with enkephalinergic receptors.

AIM

To evaluate the effects of trimebutine (50 mg intravenous injection) on the motility of the sphincter of Oddi (SO) as assessed by endoscopic manometry.

METHODS

Endoscopic manometry was performed on 15 cholecystectomized patients who presented with symptoms suggestive of SO dysfunction. Prior to the endoscopic manometry, endoscopic ultrasonography was performed in order to rule out the possible presence of a bile duct stone.

RESULTS

Injecting trimebutine resulted in a significant increase in the SO antegrade phasic contraction rate (P = 0.02). Trimebutine decreased the basal pressure of the SO (32.5 vs. 27.5 mmHg), but the difference is not statistically significant (P = 0.11). The effects of trimebutine differed depending on the basal SO motility anomalies involved, but the period of latency was similar (mean 89 s: range 30-240 s). The basal anomalies were an increased basal SO pressure of > 40 mmHg in three patients, a tachyoddia (frequency of phasic contractions (PC) > 10/min) in six patients, prolonged PC (> 10 s) in two patients and an absence of phasic contraction in one patient. The basal pressure of the SO decreased in the three patients presenting with SO hyperpressure, but returned to a normal value in one case. The frequency of the PC decreased to normal in three out of the six patients with tachyoddia. The duration of the PC returned to normal in the two patients with prolonged PC whereas their frequencies increased. Prolonged PC developed in the patient without any detectable phasic contraction.

CONCLUSIONS

Trimebutine modulates SO motility in various ways depending on the basal SO motility anomaly observed after cholecystectomy. This regulatory effect suggests the existence of encephalinergic control of SO motility.

The clinical utility of quantitative cholescintigraphy: the significance of gallbladder dysfunction

PURPOSE

Cholelithiasis is a common disorder occurring in over 20 million people in the United States and resulting in approximately 600,000 cholecystectomies annually. Although over 95% of biliary tract disease is caused by gallstones, the vast majority (>80%) of cholelithiasis cases are asymptomatic. The purpose of this study is to evaluate the utility of quantitative cholescintigraphy in detecting symptomatic biliary tract disease and predicting clinical relief after cholecystectomy.

MATERIALS AND METHODS

Fifty-two patients with clinical symptoms of chronic cholecystitis were evaluated by cholescintigraphy with a gallbladder ejection fraction calculated after the intravenous administration of cholecystokinin. A gallbladder ejection fraction of > or =35% was considered a normal physiologic response. Forty-one of the patients subsequently underwent cholecystectomy, whereas the remaining 11 subjects were diagnosed and treated for non-biliary disorders that did not require cholecystectomies. After clinical follow-up including histopathological gallbladder findings, all subjects' final diagnoses were established and correlated with their quantitative cholescintigram study.

RESULTS

Twenty-six of twenty-eight patients who had an abnormal quantitative cholescintigram demonstrated evidence of chronic cholecystitis by histopathologic criteria after cholecystectomy. Furthermore, 27 of these 28 patients (96%) experienced complete relief of their clinical symptoms after surgery.

CONCLUSION

Functional cholescintigraphy is a safe, accurate, and useful test for detecting symptomatic gallbladder disease, and appears reliable in predicting symptomatic relief after cholecystectomy.

Motility of Oddi's sphincter: recent developments and clinical applications

BACKGROUND

In recent years, applications of electromyographic, cineradiographic, scintilographic, and endoscopic manometric techniques have improved our knowledge of normal and abnormal motility of Oddi's sphincter. This sphincter coordinates the time and rate of secretion of about 3 liters of bile and pancreatic juice into the duodenum daily.

METHODS

Oddi's sphincter may be evaluated by endoscopic manometry, ultrasound, dynamic hepatobiliary scintigraphy, and laboratory tests. Endoscopic manometry is the best method for evaluating the function Oddi's sphincter.

RESULTS

The basal pressure of Oddi's sphincter is usually 5 to 15 mm Hg greater than the bile and pancreatic duct pressures. Phasic contractions of 50 to 150 mm Hg in amplitude and 3 to 8 contractions per minute in frequency are superimposed on the basal pressure. A small percentage of patients with gastrointestinal symptoms after cholecystectomy has sphincter of Oddi dysfunction, which may have structural abnormality (papillary stenosis) or functional abnormality (Oddi's sphincter dyskinesia).

CONCLUSIONS

Elevated basal pressure ( > 40 mm Hg) is the most important manometric finding of Oddi's sphincter dysfunction. Endoscopic sphincterotomy is the treatment of choice for patients with Oddi's sphincter dysfunction and elevated basal sphincter pressure.

Long-term outcome after endoscopic sphincterotomy in patients with biliary colic and suspected sphincter of Oddi dysfunction

Seventy-three highly selected patients (35 type II, 38 type III) with intractable biliary-type pain were studied with biliary manometry after a baseline endoscopic retrograde cholangiopancreatography was normal or showed only duct dilatation. No differences between the two groups were noted in regard to baseline sphincter hypertension (60% versus 55%), improvement after endoscopic sphincterotomy at mean follow-up of 3 years, or post-procedure pancreatitis rates (15% versus 16%). Although not statistically significant, a tendency for patients with bile ducts > or = 12 mm to have sustained clinical improvement after sphincterotomy was noted in comparison with patients having ducts < 12 mm; an inverse correlation between improvement in symptoms and presence of an intact gallbladder at baseline was also seen. The authors suggest that the current classification, which divides patients with recurrent right upper quadrant pain into types I, II, and III, is inadequate to define either incidence of sphincter of Oddi dysfunction or subsequent response to endoscopic sphincterotomy.

Pathophysiology of the sphincter of Oddi

Pathophysiology of the sphincter of Oddi--or sphincter of Oddi dysfunction--manifests as either a biliary-type pain syndrome or recurrent pancreatitis. Imaging studies are unreliable, and direct endoscopic manometry is used to diagnose this entity. Milwaukee biliary classification, in addition to manometry, helps guide therapy. Endoscopic sphincterotomy in selected patients achieves permanent relief of symptoms. Endoscopic therapy for recurrent pancreatitis is still experimental.

Effects of chronic morphine on biliary tract responses to cholecystokinin-octapeptide in female guinea pigs

Acute and chronic opiates impairs the emptying of bile from the gallbladder of male guinea pigs. In view of the higher incidence of gallstone attacks in women, the aim of this study was to determine if this impairment would extend to female guinea pigs. Implantation of morphine pellets (400mg) in female guinea pigs did depress CCK-induced emptying of gallbladder bile. Likewise, gallbladder muscle strips isolated from the morphine treated animals showed depressed responses to CCK. The morphine treatment also antagonized CCK-induced cessation of bile flow present in female guinea pigs. In addition, the morphine treatment blocked both CCK-induced phasic contractions of the isolated isolated Sphincter of Oddi and the secondary cessation of bile flow observed following iv CCK. Thus this study demonstrates that opiate antagonism of CCK does extend to the biliary tract of female guinea pigs, and suggests that resultant biliary stasis could facilitate gallstone formation.

Pathogenesis of gallstones

The many developments in nonoperative methods for the treatment of gallstone disease underscore the importance of understanding the pathogenesis of these stones. Elucidation of the factors responsible for nucleation of crystals and the mechanism by which it occurs would appear to be the challenge if we are to define the cascade of events that results in gallstone formation.

Radiation-induced changes in mouse duodenal papilla

Radiation-induced changes in duodenal mucosal morphology as seen by scanning electron microscopy have been widely reported in the literature. However, no comment has previously been made on any post-irradiation alteration in the duodenal papilla. This paper describes the preliminary results of an investigation into the effects of X rays on the papilla. The duodenal papilla was difficult to find in untreated and sham irradiated mice. It was identified in only two of six mice examined and was located 5.37 and 4.43 mm from the gastroduodenal junction. Eighteen hours after irradiation with 15 Gy X rays, there was little change in position or prominence of the papilla. However, 3 days after treatment, the papilla was only 2.19-3.83 mm from the pylorus. It was also more prominent, being found in all three animals studied and having a widely dilated orifice in contrast to the closed structure seen in the unirradiated specimens. It is concluded that treatment with X rays alters the structure of the duodenal papilla. There may be implications for duodenal function in this marked change in the papilla, which controls the flow of pancreatic and biliary secretions.