Sphincter of Oddi Dysfunction Induces Gallstone by Inhibiting the Expression of ABCB11 via PKC-α

The abnormal increase of Oddi sphincter pressure and total bile duct pressure may play an important role in the formation of cholesterol stones, but the specific molecular mechanism is still unclear. This study aims to investigate it through in vitro and in vivo experiments. A mouse model of Oddi sphincter dysfunction was constructed by stone-inducing diet. We compared the two groups with PKC-α inhibitor GÖ6976 and PKC-α agonist thymeleatoxin. Oddi sphincter pressure and total bile duct pressure were measured. Biochemical analysis of total cholesterol, bile acid and bilirubin was then conducted. The histopathologic changes of bile duct were observed by HE staining and the ultrastructure of liver cells and surrounding tissues was observed by transmission electron microscopy. Through the above experiments, we found that the change of PKC-α expression may affect the formation process of gallstones. The relationship between PKC-α and ABCB11 was further verified by in vitro and in vivo experiments. Our results suggest that ABCB11 and PKC-α are co-expressed in the tubule membrane of hepatocytes and interact with each other in hepatocytes. The high cholesterol diet further enhances the activation of PKC-α and thus reduces the expression of ABCB11. The formation of cholesterol stones is associated with the down-regulation of ABCB11 expression in the tubule membrane of hepatocytes due to kinase signaling. This is the first study to demonstrate that sphincter of Oddi dysfunction induces gallstones through PKC-α inhibition of ABCB11 expression.

The efficacy and safety of endoscopic sphincterotomy in patients with Sphincter of Oddi dysfunction: a systematic review and meta-analysis

OBJECTIVE

Sphincter of Oddi dysfunction (SOD) has been used to describe patients with RUQ abdominal pain without an etiology. We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of ES (endoscopic sphincterotomy) for SOD.

METHODS

The study methodology follows the PRISMA guidelines. A comprehensive search was conducted using MEDLINE and EMBASE databases for RCTs with ES in patients with SOD. The primary outcome assessed was the improvement of abdominal pain after ES/sham. A random effects model was used to calculate pooled estimates for each outcome of interest.

RESULTS

Of the initial 55 studies, 23 were screened and thoroughly reviewed. The final analysis included 3 studies. 340 patients (89.7% women) with SOD were included. All patients had a cholecystectomy. Most included patients had SOD type II and III. The pooled rate of technical success of ERCP was 100%. The average clinical success rate was 50%. The pooled cumulative rate of overall AEs related to all ERCP procedures was 14.6%. In the sensitivity analysis, only one study significantly affected the outcome or the heterogeneity.

CONCLUSION

ES appears no better than placebo in patients with SOD type III. Sphincterotomy could be considered in patients with SOD type II and elevated SO basal pressure.

Meta-analysis on clinical outcomes of suprapapillary versus transpapillary stent insertion in malignant biliary obstruction

BACKGROUND/AIMS

Endoscopic biliary stenting is an essential treatment for malignant biliary obstruction (MBO). However, the optimal location for the placement of metal stents (MS) or plastic stents (PS) during the management of MBO, whether above (suprapapillary) or across (transpapillary) the sphincter of Oddi (SO), has not been thoroughly evaluated. This meta-analysis aims to compare the clinical outcomes associated with endoscopic retrograde cholangiopancreatography (ERCP)-guided biliary stents placed above and across the SO in patients with MBO.

METHODS

A comprehensive search of electronic databases was carried out to identify studies published from inception to April 2022. The clinical outcomes examined including stent patency, stent occlusion, and overall adverse events (AEs) such as cholangitis, post-ERCP pancreatitis (PEP), cholecystitis, stent migration, and bleeding. The selection of a random-effects model or fixed-effects model was based on the presence of heterogeneity.

RESULTS

A total of 12 articles involving 751 patients were analyzed. The findings showed that the suprapapillary approach had longer stent patency compared to the transpapillary approach (mean difference: 38.58; 95% confidence interval 16.02-61.14, P < 0.0001). Additionally, the suprapapillary approach was associated with a lower risk of stent occlusion and overall AEs (P = 0.04, P = 0.002, respectively), particularly in the incidence of PEP (P = 0.009). The incidence of cholangitis, cholecystitis, stent migration, and bleeding were similar between the suprapapillary and transpapillary approaches. The subgroup analyses indicated that suprapillary PS had a significant decrease in the incidence of stent occlusion and longer stent patency, while suprapillary MS had a significant decrease in the incidence of overall AEs and PEP than the transpapillary approach.

CONCLUSION

Compared with the transpapillary approach, the suprapapillary stent had superiority in longer stent patency, lower rates of stent occlusion and overall AEs, and notably, a lower incidence of PEP. The incidence of cholangitis, cholecystitis, stent migration, and bleeding were similar between the suprapapillary and transpapillary approaches. Further large-scale randomized controlled studies are needed to confirm our findings.

REGISTRATION NO

CRD42022336435.

Sphincter of Oddi incompetence associated with duodenal stenosis in a newborn: A case report

Newborn incompetence of the sphincter of Oddi is rare. While there are many causes of reflux of air or ingested contrast material into the biliary tree in adults, in the newborn, it is usually due to incompetence of the sphincter of Oddi associated with partial or complete duodenal obstruction. This paper presents upper gastrointestinal series findings of incompetence of the sphincter of Oddi associated with duodenal stenosis in a 3-day-old newborn. If pneumobilia is identified in the newborn, although the possibility is low, clinicians should consider incompetence of the sphincter of Oddi with duodenal obstruction as well as portal vein gas.

The unknown and misunderstood life of Ruggero Oddi, the pioneer of biliary system physiology

Ruggero Oddi was a talented scientist who initiated the modern era of biliary system physiology, not only with the anatomical discovery of the hepatopancreatic sphincter, but also with the detailed description of its spinal center and nerve regulation. However, his personal and scientific life were determined by an incredible series of unfortunate circumstances. Until now most of these events have been unknown, while the few known have produced biographies distorted by fake interpretations. The purpose of this article is to document Oddi's biography and scientific production in detail, comprehensively framing the scientific environment in which his discoveries occurred. It clears many misinterpretations about events in Oddi's life and academic career, bringing to a new light his figure as scientist in gastroenterological field.

Update on Sphincter of Oddi Dysfunction: A Review

Sphincter of Oddi dysfunction (SOD) encompasses a spectrum of clinical syndromes that are not fully understood, and various diagnostic and therapeutic methods have had varying results depending on the type of dysfunction. This review explored various mechanisms that might play a role in SOD and methods of diagnosis and management. It is important to rule out other causes of abdominal pain with laboratory testing, imaging studies, and endoscopic procedures. Medications that affect sphincter motility should be identified as well. Manometry is the gold standard for diagnosis but it is not always required. For example, patients with type I SOD may have symptomatic improvement with sphincterotomy without need for a diagnostic manometry. Hepatobiliary scintigraphy and fatty meal sonography may also have diagnostic utility. Sphincterotomy is not always effective for symptomatic improvement in type II and III SOD. Alternate therapies with calcium channel blockers and botulinum toxin have been studied and might be considered as options after discussing the risks and benefits with the patients.

Immunohistochemical staining for IMP3 in patients with duodenal papilla tumors: assessment of the potential for diagnosing endoscopic resectability and predicting prognosis

BACKGROUND

Endoscopic papillectomy of duodenal papillary tumors (PT) is indicated for adenomas or well-differentiated adenocarcinomas that do not involve the sphincter of Oddi. However, there is currently no reliable pre-operative method to diagnose the infiltration in the sphincter of Oddi.' Insulin-like growth factor 2 mRNA protein 3 (IMP3) staining is reportedly associated with advanced disease stage and clinical outcomes in many carcinomas. The aim of this retrospective study was to investigate the ability of diagnosing sphincter of Oddi involvement in PT and predicting the prognoses using IMP3 immunohistochemistry.

METHODS

Twenty-five resected specimens from patients with PT and 24 biopsy specimens from the same patients excluding one were immunostained for IMP3. The percentage of positive cells in the tumor was evaluated and compared with the final pathological diagnosis and prognosis.

RESULTS

The final pathological diagnoses were adenoma in 5 patients and adenocarcinoma in 20 patients (no sphincter of Oddi involvement in 5 and involvement in 15). The ability to diagnose sphincter of Oddi involvement based on the percentage of IMP3-positive cells in resected specimens and tissue biopsies was the area under the curve 0.8 and 0.78, respectively, of the receiver operating characteristic curve, and the accuracies were 80.0% and 75.0% (cutoff value: 10%), respectively. Moreover, patients with an IMP3-positive cell rate of ≥ 10% had a significantly worse prognosis (log-rank test P = 0.01).

CONCLUSION

IMP3 immunostaining of resected and biopsy specimens from PT patients enables the diagnosis of sphincter of Oddi involvement objectively and is also effective in predicting the prognosis.

Axin2+ Peribiliary Glands in the Periampullary Region Generate Biliary Epithelial Stem Cells That Give Rise to Ampullary Carcinoma

BACKGROUND & AIMS

Peribiliary glands (PBGs), clusters of epithelial cells residing in the submucosal compartment of extrahepatic bile ducts, have been suggested as biliary epithelial stem/progenitor cell niche; however, evidence to support this claim is limited because of a lack of PBG-specific markers. We therefore sought to identify PBG-specific markers to investigate the potential role of PBGs as stem/progenitor cell niches, as well as an origin of cancer.

METHODS

We examined the expression pattern of the Wnt target gene Axin2 in extrahepatic bile ducts. We then applied lineage tracing to investigate whether Axin2-expressing cells from PBGs contribute to biliary regeneration and carcinogenesis using Axin2-Cre^ERT mice.

RESULTS

Wnt signaling activation, marked by Axin2, was limited to PBGs located in the periampullary region. Lineage tracing showed that Axin2-expressing periampullary PBG cells are capable of self-renewal and supplying new biliary epithelial cells (BECs) to the luminal surface. Additionally, the expression pattern of Axin2 and the mature ductal cell marker CK19 were mutually exclusive in periampullary region, and fate tracing of CK19⁺ luminal surface BECs showed gradual replacement by CK19^- cells, further supporting the continuous replenishment of new BECs from PBGs to the luminal surface. We also found that Wnt signal enhancer R-spondin3 secreted from Myh11-expressing stromal cells, corresponding to human sphincter of Oddi, maintained the periampullary Wnt signal-activating niche. Notably, introduction of PTEN deletion into Axin2⁺ PBG cells, but not CK19⁺ luminal surface BECs, induced ampullary carcinoma whose development was suppressed by Wnt inhibitor.

CONCLUSION

A specific cell population receiving Wnt-activating signal in periampullary PBGs functions as biliary epithelial stem/progenitor cells and also the cellular origin of ampullary carcinoma.

Elevated Lipase in an Infant with Altered Mental Status

The pancreatic enzymes lipase and amylase serve important functions in digestion/absorption of fats and polysaccharides. Measurement of these enzymes is often used in the emergency department to rule out acute pancreatitis in patients with nonspecific abdominal pain. In acute pancreatitis, serial measurements of plasma lipase and amylase typically follow a predictable temporal pattern of rise-and-fall kinetics: lipase levels rise within 4 to 8 hours, crest at 2× to 50× the upper reference limit at 24 hours, and decline to normal concentrations in 7 to 14 days. In situations in which the duration and magnitude of pancreatic enzyme elevation are more transient, clinicians should consider alternative causes for enzyme elevation. In this case report, incidental discovery of elevated lipase in an African American baby girl who ingested oxycodone resulted in additional laboratory and radiological work-up. Stronger awareness of exogenous influences on gastrointestinal motility may have prevented the need for further testing in this patient.

Modified percutaneous transhepatic papillary balloon dilation for patients with refractory hepatolithiasis

BACKGROUND

Some patients with hepatolithiasis cannot tolerate surgery due to severe cardiac or pulmonary comorbidities, or cannot be endoscopically treated because of altered gastrointestinal anatomies.

AIM

To propose a modified percutaneous transhepatic papillary balloon dilation procedure, and evaluate the clinical efficacy and safety of this modality.

METHODS

Data from 21 consecutive patients who underwent modified percutaneous transhepatic papillary balloon dilation with hepatolithiasis were retrospectively analyzed. Using auxiliary devices, intrahepatic bile duct stones were pushed into the common bile duct and expelled into the duodenum with an inflated balloon catheter. The outcomes recorded included success rate, procedure time, hospital stay, causes of failure, and procedure-related complications. Patients with possible long-term complications were followed up for 2 years.

RESULTS

Intrahepatic bile duct stones were successfully removed in 20 (95.23%) patients. Mean procedure time was 65.8 ± 5.3 min. Mean hospital stay was 10.7 ± 1.5 d. No pancreatitis, gastrointestinal, or biliary duct perforation was observed. All patients were followed up for 2 years, and there was no evidence of reflux cholangitis or calculi recurrence.

CONCLUSION

Modified percutaneous transhepatic papillary balloon dilation was feasible and safe with a small number of patients with hepatolithiasis, and may be a treatment option in patients with severe comorbidities or in patients in whom endoscopic procedure was not successful.

T-tube drainage versus choledochojejunostomy in hepatolithiasis patients with sphincter of Oddi laxity: study protocol for a randomized controlled trial

Background

Residual and recurrent stones remain one of the most important challenges of hepatolithiasis and are reported in 20 to 50% of patients treated for this condition. To date, the two most common surgical procedures performed for hepatolithiasis are choledochojejunostomy and T-tube drainage for biliary drainage. The goal of the present study was to evaluate the therapeutic safety and perioperative and long-term outcomes of choledochojejunostomy versus T-tube drainage for hepatolithiasis patients with sphincter of Oddi laxity (SOL).

Methods/design

In total, 210 patients who met the following eligibility criteria were included and were randomized to the choledochojejunostomy arm or T-tube drainage arm in a 1:1 ratio: (1) diagnosed with hepatolithiasis with SOL during surgery; (2) underwent foci removal, stone extraction and stricture correction during the operation; (3) provided written informed consent; (4) was willing to complete a 3-year follow-up; and (5) aged between 18 and 70 years. The primary efficacy endpoint of the trial will be the incidence of biliary complications (stone recurrence, biliary stricture, cholangitis) during the 3 years after surgery. The secondary outcomes will be the surgical, perioperative and long-term follow-up outcomes.

Discussion

This is a prospective, single-centre and randomized controlled two-group parallel trial designed to demonstrate which drainage method (Roux-en-Y hepaticojejunostomy or T-tube drainage) can better reduce biliary complications (stone recurrence, biliary stricture, cholangitis) in hepatolithiasis patients with SOL.

Trial registration

Clinical Trials.gov: NCT04218669. Registered on 6 January 2020.

Increased Risk of Acute Pancreatitis with Codeine Use in Patients with a History of Cholecystectomy

BACKGROUND

Codeine has a spasmodic effect on sphincter of Oddi and is suspected to cause acute pancreatitis in patients with a history of cholecystectomy.

AIMS

To assess the association between codeine use and acute pancreatitis in patients with a previous cholecystectomy.

METHODS

We conducted a retrospective nested case-control study using the 2005-2015 MarketScan^® Commercial Claims and Encounters Database. The cohort included patients aged 18-64; cohort entry began 365 days after cholecystectomy. Odds ratios (ORs) and 95% CIs for acute pancreatitis hospitalization were estimated comparing use of codeine with non-use of codeine. In a secondary analysis, use of codeine was compared with an active comparator: use of non-steroidal anti-inflammatory drugs (NSAIDs).

RESULTS

Of the 664,083 patients included in the cohort, 1707 patients were hospitalized for acute pancreatitis (incidence 1.1 per 1000 person-years) and were matched to 17,063 controls. Compared with non-use of codeine, use of codeine was associated with an increased risk of acute pancreatitis (OR 2.67; 95% CI 1.63, 4.36), particularly elevated in the first 15 days of codeine use (OR 5.37; 95% CI 2.70, 10.68). Compared with use of NSAIDs, use of codeine was also associated with an increased risk of acute pancreatitis (OR 2.64; 95% CI 1.54, 4.52).

CONCLUSION

Codeine is associated with an increased risk of acute pancreatitis in patients who have previously undergone cholecystectomy; greater clinician awareness of this association is needed.

Cyclic Change of Sphincter of Oddi Motility and Its Relationship with Small Bowel Migrating Motor Complex in Humans

BACKGROUND

Several animal and human studies have reported that sphincter of Oddi (SO) motility shows cyclical changes during the fasting state. However, to date, the relationship between the SO motility and the migrating motor complex (MMC) of the small bowel (SB) remains unclear in humans.

AIMS

We observed SO motility over a long study period and evaluated its relationship with the MMC of the SB in humans using percutaneous long-term manometry.

METHODS

Our study included patients with hepatolithiasis who required percutaneous transhepatic catheter placement and subsequently underwent choledochoscopy and stone removal. Long-term percutaneous transhepatic SO manometry was performed after complete stone removal. SO and SB motility were simultaneously recorded.

RESULTS

SO motility showed cyclical phasic changes with periodic high-frequency contractions similar to the MMC contractions of the SB. All high-frequency contractions of the SO coincided with phase III contractions of the MMC of the SB. The proportions of phase III contractions of SO and SB were similar, but the proportions of phase I (P = 0.001) and phase II (P = 0.002) contractions were significantly different. The mean basal SO pressure was observed to significantly increase in phase III compared to phase I (P = 0.001) and phase II (P = 0.001) contractions.

CONCLUSIONS

SO motility in humans showed cyclical phasic changes closely coordinated with the MMC of the SB in a fasting state; however, the proportion of phases differed between the SO and the SB. The basal pressure significantly increased during physiological high-frequency phase III contractions of the SO.

The prevalence and correlation between subclinical hypothyroidism and gall stone disease in Baghdad teaching hospital

Background

Gall stones are the most common biliary pathology. Subclinical hypothyroidism is not a common problem in the population with thyroid disease, several explanations for a possible relation between hypothyroidism and lipid metabolism, gall stone formation proved that prevalence of gall stones is increased in patients with hypothyroidism disease.

Objective

To find the prevalence and correlation between the subclinical hypothyroidism and gall stone disease.

Methods

This cross-sectional study in Baghdad teaching hospital which done over the period of January 2015 till December 2015 where 103 patients presented with gall stones as an in and outpatients. All the patients were assessed and prepared for cholecystectomy by detailed history, clinical examination, thyroid function test and abdominal ultrasound.

Results

Among 103 patients, the majority them were in 36-50 years age group, 84 (81.6%) of them were females and 19 (18.4%) were males. Of the total number of patients, eight of them (7.8%) found to have subclinical hypothyroidism and 95 (92.2%) of them found to be euthyroid, most of patients in the subclinical hypothyroid group were showing female gender predominance with 81.6%. While the prevalence among males were found 18.4%, most patients with subclinical hypothyroidism were found to had positive family history (75%), and (25%) of them found to had negative family history.

Conclusion

There is gender specific relationship between subclinical hypothyroidism and gall stone disease as this study sharing statistically increasing in prevalence of the subclinical hypothyroidism among females in age group ≥ 40 years, positive family history, and single abdominal US gall stone. This subset of patients should be assessed for thyroid dysfunction.

Current situation and problems in diagnosis and treatment of sphincter of Oddi dysfunction

Sphincter of Oddi dysfunction (SOD) is a clinical syndrome referring to the loss of normal physiological function of the sphincter of Oddi with upper abdominal pain from the gallbladder and pancreas, postprandial abdominal bloating, elevation of liver or pancreatic enzymes, common bile duct dilation, pancreatitis and so on. SOD is more common in patients after cholecystectomy. Although the established criteria for diagnosing and treating SOD have been applied in clinical practice, its diagnosis and treatment have long been a controversial topic since the best diagnostic and treatment methods are still unconfirmed, partly because of its natural course, disease treatment process, and long-term follow-up outcomes that have not been determined in large controlled studies. This article briefly reviews the latest research of SOD and comprehensively analyzes the current status and existing problems in the diagnosis and treatment of SOD, with an aim to provide appropriate advice for clinicians to diagnose and treat this disease.

Sphincter of Oddi Dysfunction: A Perplexing Presentation

Sphincter of Oddi dysfunction is caused by stenosis or dyskinesia of the sphincter of Oddi, leading to blockage of bile drainage from the common bile duct. We present the case of a 16-year-old female with chronic abdominal pain who underwent laparoscopic cholecystectomy for cholelithiasis but continued to experience abdominal pain, nausea, and vomiting along with persistently elevated ALT and AST levels. Postoperative abdominal ultrasound was nondiagnostic. Esophagogastroduodenoscopy showed mild reflux esophagitis and mild chronic Helicobacter pylori-negative gastritis. Omeprazole was started, but it did not decrease the frequency and severity of the abdominal symptoms. Magnetic resonance cholangiopancreatography did not reveal any pathology. Endoscopic retrograde cholangiopancreatography with manometry confirmed an elevated biliary sphincter pressure. Biliary sphincterotomy was performed, and the symptoms improved.

Effects of sphincter of Oddi motility on the formation of cholesterol gallstones

AIM: To investigate the mechanisms and effects of sphincter of Oddi (SO) motility on cholesterol gallbladder stone formation in guinea pigs.

METHODS: Thirty-four adult male Hartley guinea pigs were divided randomly into two groups, the control group (n = 10) and the cholesterol gallstone group (n = 24), which was sequentially divided into four subgroups with six guinea pigs each according to time of sacrifice. The guinea pigs in the cholesterol gallstone group were fed a cholesterol lithogenic diet and sacrificed after 3, 6, 9, and 12 wk. SO manometry and recording of myoelectric activity were obtained by a multifunctional physiograph at each stage. Cholecystokinin-A receptor (CCKAR) expression levels in SO smooth muscle were detected by quantitative real-time PCR (qRT-PCR) and serum vasoactive intestinal peptide (VIP), gastrin, and cholecystokinin octapeptide (CCK-8) were detected by enzyme-linked immunosorbent assay at each stage in the process of cholesterol gallstone formation.

RESULTS: The gallstone formation rate was 0%, 0%, 16.7%, and 83.3% in the 3, 6, 9, and 12 wk groups, respectively. The frequency of myoelectric activity in the 9 wk group, the amplitude of myoelectric activity in the 9 and 12 wk groups, and the amplitude and the frequency of SO in the 9 wk group were all significantly decreased compared to the control group. The SO basal pressure and common bile duct pressure increased markedly in the 12 wk group, and the CCKAR expression levels increased in the 6 and 12 wk groups compared to the control group. Serum VIP was elevated significantly in the 9 and 12 wk groups and gastrin decreased significantly in the 3 and 9 wk groups. There was no difference in serum CCK-8 between the groups.

CONCLUSION: A cholesterol gallstone-causing diet can induce SO dysfunction. The increasing tension of the SO along with its decreasing activity may play an important role in cholesterol gallstone formation. Expression changes of CCKAR in SO smooth muscle and serum VIP and CCK-8 may be important causes of SO dysfunction.

Effects of remifentanil on the sphincter of Oddi in a 3-year-old child: a case report

Opioids cause spasm of the sphincter of Oddi. Remifentanil is metabolized enzymatically throughout the body. Its context-sensitive half-time is 3 to 4minutes. The effect of remifentanil on the sphincter of Oddi is unknown, especially in children. We recently encountered a patient in whom the administration of remifentanil caused spasm of the sphincter of Oddi, which resolved rapidly after discontinuation of remifentanil. A 3-year-old girl weighing 11.3kg was scheduled to undergo common bile duct excision with ductoplasty. Her diagnosis was congenital biliary dilatation. In the operating room, after achieving the initial induction through sevoflurane (5%) and intravenous rocuronium (10mg), she was intubated and administered a continuous paravertebral block by levobupivacaine (25mg/10mL +2.5mg/h). General anesthesia was maintained with sevoflurane (2%), remifentanil (0.5 μg kg(-1) min(-1)), and oxygen (fractional inspired oxygen tension, 0.33). The first intraoperative cholangiogram obtained via the cystic duct tube showed obstruction at the terminal end of the common bile duct. We injected scopolamine butylbromide (5mg, intravenous) to relax the sphincter of Oddi. However, the next cholangiogram obtained 3minutes later still showed an obstruction. We speculated that the obstruction may have been caused by remifentanil-induced spasm of the sphincter of Oddi. Therefore, we stopped administering remifentanil; 2minutes later, we achieved satisfactory passage of the contrast material to the duodenum. The predicted plasma concentrations of remifentanil at the time of stopping its administration and at the time of disobliteration were 6.38and 2.55ng/mL, respectively. The patient's postoperative course was uneventful. In patients who have spasms of the sphincter of Oddi during the administration of remifentanil, the resultant obstruction can be treated effectively by reducing the infusion rate of remifentanil.

Oddi sphincter preserved cholangioplasty with hepatico-subcutaneous stoma for hepatolithiasis

AIM: To evaluate the long-term outcomes of Oddi sphincter preserved cholangioplasty with hepatico-subcutaneous stoma (OSPCHS) and risk factors for recurrence in hepatolithiasis.

METHODS: From March 1993 to December 2012, 202 consecutive patients with hepatolithiasis underwent OSPCHS at our department. The Oddi sphincter preserved procedure consisted of common hepatic duct exploration, stone extraction, hilar bile duct plasty, establishment of subcutaneous stoma to the bile duct. Patients with recurrent stones can undergo stone extraction and/or biliary drainage via the subcutaneous stoma which can be incised under local anesthesia. The long-term results were reviewed. Cox regression model was employed to analyze the risk factors for stone recurrence.

RESULTS: Ninety-seven (48.0%) OSPCHS patients underwent hepatic resection concomitantly. The rate of surgical complications was 10.4%. There was no perioperative death. The immediate stone clearance rate was 72.8%. Postoperative cholangioscopic lithotomy raised the clearance rate to 97.0%. With a median follow-up period of 78.5 mo (range: 2-233 mo), 24.8% of patients had recurrent stones, 2.5% had late development of cholangiocarcinoma, and the mortality rate was 5.4%. Removal of recurrent stones and/or drainage of inflammatory bile via subcutaneous stoma were conducted in 44 (21.8%) patients. The clearance rate of recurrent stones was 84.0% after subsequent choledochoscopic lithotripsy via subcutaneous stoma. Cox regression analysis showed that residual stone was an independent prognostic factor for stone recurrence.

CONCLUSION: In selected patients with hepatolithiasis, OSPCHS achieves excellent long-term outcomes, and residual stone is an independent prognostic factor for stone recurrence.

Effects of thienorphine on contraction of the guinea pig sphincter of Oddi, choledochus and gall bladder

Opioid analgesics are widely believed to cause spasm of the bile duct sphincter and so impede bile flow. Thienorphine is a partial opioid agonist that is a good candidate for the treatment of opioid dependence; however, to date, no studies have reported the effects of thienorphine on the function of the biliary tract. This study examined the in vivo effects of thienorphine on the guinea pig isolated sphincter of Oddi, choledochus and gall bladder and on bile flow. The area under the curve (AUC) of isolated sphincter of Oddi was not influenced by thienorphine or buprenorphine, whereas morphine increased the AUC of the isolated sphincter of Oddi in a concentration-dependent manner. Thienorphine and buprenorphine concentration-dependently decreased the AUC of isolated choledochus, while morphine increased the AUC of isolated choledochus. Thienorphine had no effect on the contractile amplitude or basal tension of isolated gall bladder muscle strips. In contrast, buprenorphine and morphine increased the contractile basal tension of isolated gall bladder muscle strips in a concentration-dependent manner. Thienorphine (0.01-1.0mg/kg) had no significant inhibitory effect on bile flow. However, morphine (1.0-10mg/kg) and buprenorphine (1.0mg/kg) significantly inhibited bile flow. The maximum inhibition of bile flow by buprenorphine was 63.9±12.9% and by morphine was 74.1±11.3%. In summary, thienorphine has little influence on the guinea pig isolated sphincter of Oddi, choledochus and gall bladder or on bile flow, which may result in a lack of adverse biliary colic effects.

Roles of sphincter of Oddi motility and serum vasoactive intestinal peptide, gastrin and cholecystokinin octapeptide

AIM: To investigate roles of sphincter of Oddi (SO) motility played in pigment gallbladder stone formation in model of guinea pigs.

METHODS: Thirty-four adult male Hartley guinea pigs were divided randomly into two groups: the control group and pigment stone group. The pigment stone group was divided into 4 subgroups with 6 guinea pigs each according to time of sacrifice, and were fed a pigment lithogenic diet and sacrificed after 3, 6, 9 and 12 wk. SO manometry and recording of myoelectric activity of the guinea pigs were obtained by multifunctional physiograph at each stage. Serum vasoactive intestinal peptide (VIP), gastrin and cholecystokinin octapeptide (CCK-8) were detected at each stage in the process of pigment gallbladder stone formation by enzyme-linked immunosorbent assay.

RESULTS: The incidence of pigment gallstone formation was 0%, 0%, 16.7% and 66.7% in the 3-, 6-, 9- and 12-wk group, respectively. The frequency of myoelectric activity decreased in the 3-wk group. The amplitude of myoelectric activity had a tendency to decrease but not significantly. The frequency of the SO decreased significantly in the 9-wk group. The SO basal pressure and common bile duct pressure increased in the 12-wk group (25.19 ± 7.77 mmHg vs 40.56 ± 11.81 mmHg, 22.35 ± 7.60 mmHg vs 38.51 ± 11.57 mmHg, P < 0.05). Serum VIP was significantly elevated in the 6- and 12-wk groups and serum CCK-8 was decreased significantly in the 12-wk group.

CONCLUSION: Pigment gallstone-causing diet may induce SO dysfunction. The tension of the SO increased. The disturbance in SO motility may play a role in pigment gallstone formation, and changes in serum VIP and CCK-8 may be important causes of SO dysfunction.

Imaging pancreatobiliary ductal system with optical coherence tomography: A review

An accurate, noninvasive and cost-effective method of in situ tissue evaluation during endoscopy would be highly advantageous for the detection of dysplasia or early cancer and for identifying different disease stages. Optical coherence tomography (OCT) is a noninvasive, high-resolution (1-10 μm) emerging optical imaging method with potential for identifying microscopic subsurface features in the pancreatic and biliary ductal system. Tissue microstructure of pancreaticobiliary ductal system has been successfully imaged by inserting an OCT probe through a standard endoscope operative channel. High-resolution OCT images and the technique’s endoscopic compatibility have allowed for the microstructural diagnostic of the pancreatobiliary diseases. In this review, we discussed currently available pancreaticobiliary ductal imaging systems to assess the pancreatobiliary tissue microstructure and to evaluate varieties of pancreaticobiliary disorders and diseases. Results show that OCT can improve the quality of images of pancreatobiliary system during endoscopic retrograde cholangiopancheatography procedure, which may be important in distinguishing between the neoplastic and non-neoplastic lesions.

Severe acute cholangitis after endoscopic sphincterotomy induced by barium examination: A case report

Endoscopic sphincterotomy (EST) is considered as a possible etiological factor for severe cholangitis. We herein report a case of severe cholangitis after endoscopic sphincterotomy induced by barium examination. An adult male patient presented with epigastric pain was diagnosed as having choledocholithiasis by ultrasonography. EST was performed and the stone was completely cleaned. Barium examination was done 3 d after EST and severe cholangitis appeared 4 h later. The patient was recovered after treated with tienam for 4 d. Barium examination may induce severe cholangitis in patients after EST, although rare, barium examination should be chosen cautiously. Cautions should be also used when EST is performed in patients younger than 50 years to avoid the damage to the sphincter of Oddi.

Morphometric development of sphincter of oddi in human fetuses during fetal period: microscopic study

OBJECTIVE

In this study, morphometric developments of the sphincter of Oddi in human fetuses were observed.

MATERIAL AND METHODS

We observed 113 human fetuses consisting of 67 male and 46 female subjects, whose ages varied between 14 to 40 weeks who showed no signs of any pathology or anomaly externally. The common external measurements of fetuses were carried out, followed by abdominal dissection to determine where the sphincters of Oddi were localized within the duodenum and pancreas. Histological specimens of tissue samples were gathered from the inner wall of the duodenum where it was assumed that the sphincters of Oddi had been localized. The parameters of total external diameters, lumen diameters, wall thickness, diameters of ductus choledochus and ductus pancreaticus, and the distance between these two structures, which are also known as the origins of the sphincter of Oddi, were measured by using a light microscope. The standard deviations of the measurements were calculated for each gestational week and trimester.

RESULTS

The calculations suggested that there were statistically significant correlations between gestational age and all of the other parameters with the exception of the ductus choledochus (p<0.001). It was observed that the wall thickness of the ductus choledochus increased at the first half of the fetal stage and decreased at the second half, as the lumen diameter increased through the 40th week. The gender difference was not statistically significant (p>0.05).

CONCLUSION

The data we collected in our study were considered as useful for the evaluation of the development of the sphincter of Oddi area and fetal stage.

How to interpret a functional or motility test - sphincter of oddi manometry

To date, endoscopic manometry is the best method for evaluating the function of the sphincter. Sphincter of Oddi manometry (SOM) remains the gold standard to correctly diagnose the sphincter of Oddi dysfunction (SOD) and stratify therapy. Several dynamic abnormalities relating to the intensity, frequency, and propagation of sphincter contractions have been described. However, their clinical use generally has been abandoned in favor of basal sphincter pressure alone, because this measurement is stable over time, and has stronger interobserver reliablility, reproducibility on repeating testing, and is associated with the responsiveness to therapy. A significant elevated risk of pancreatitis was attributed to the technique. The risk of pancreatitits associated with manometric evaluation of the pancreatic sphincter is markedly reduced when manometry is performed with continous aspiration from the pancreatic duct via one of the 3 catheter lumens. This section reviews indications, conscious sedative drugs, techniques, and the appropriate interpretations of SOM.

Pancreaticobiliary reflux in patients with a normal pancreaticobiliary junction: Pathologic implications

Knowledge on pancreaticobiliary reflux in normal pancreaticobiliary junction and its pathologic implications has experienced tremendous progress during the last few years. This editorial reviews the current knowledge on this condition and its pathological implications on gallbladder diseases. The following aspects were defined appropriate for discussion: (1) Evidence of carcinogenesis associated with pancreaticobiliary reflux; (2) Evidence of pancreaticobiliary reflux in normal pancreaticobiliary junction; and (3) Evidence of sphincter of Oddi (SO) dysfunction as a cause of pancreaticobiliary reflux in normal pancreaticobiliary junction. The articles reviewed were selected and classified according to five levels of evidence: LevelI, meta-analysis double-blind randomized clinical trials, Level II, cohort non-blinded studies and non-randomized clinical trials, Level III, good quality case-control studies and non-randomized cohort studies, Level IV, case series and poor quality case-control studies, and Level V, case report articles and experts’ opinion. Evidence levels II, III, IV and V were found to support biliary carcinogenesis associated with pancreaticobiliary reflux in normal and abnormal pancreaticobiliary junction. The same levels of evidence were found to support the common occurrence of pancreaticobiliary reflux in normal pancreaticobiliary junction, and SO dysfunction as the most plausible cause of this condition. Although an important body of research has been published regarding pancreaticobiliary reflux in normal pancreaticobiliary junction and its clinical significance, the current evidence does not fully support what has been suggested. Studies with evidence level I have not been undertaken. This is a fascinating subject of study, and if finally supported by evidence level I, the importance of this condition will constitute a major breakthrough in biliary pathology.

Effects of gastrokinetic agents on human sphincter of Oddi motility

AIM: To observe the effects of domperidone, mosapride and tegaserod on the motility of human sphincter of Oddi (SO) and to analyze potential mechanisms involved.

METHODS: Thirty-two patients with T-tube drainage after choledochotomy were randomly divided into three groups: domperidone group, mosapride group and tegaserod group. The pressure of the SO was measured with a choledochofiberscope via T-tube fistula. Agents were given sublingually. Basic pressure of the SO (SOBP), amplitude of the SO (SOCA), duration of phasic contractions (SOD), duodenal pressure (DP), and common bile duct pressure (CBDP) were recorded and analyzed.

RESULTS: SOBP and SOCA decreased markedly not only in the domperidone group (10.30 ± 4.99 vs 6.40 ± 3.66; 110.52 ± 37.80 vs 68.67 ± 41.02; both P < 0.05) but also in the mosapride group (2.56 ± 13.02 vs 6.00 ± 5.74; 83.44 ± 46.16 vs 52.48 ± 44.19; both P < 0.05). SOBP and SOCA did not change after tegaserod intake. No significant changes in SOF, SOD and CBDP were noted in all the groups.

CONCLUSION: Both domperidone and mosapride at clinical doses decrease SOBP and SOCA and inhibit SO motility, while tegaserod at clinical dose does not affect SO motility.

Effect of somatostatin on human sphincter of Oddi motility

Native somatostatin is a gut hormone and neuropeptide, widely distributed in the nervous and gastrointestinal system, and has a broad range of biological actions. In gastrointestinal tract (GIT), somatostatin is mainly produced by the delta cells of the pancreas and gastrointestinal mucosal. The inhibitory effects of somatostatin on gastrointestinal motility and hormone secretion are mediated by a family of G protein-coupled receptors: the somatostatin receptors (SSTR1-5). The sphincter of Oddi (SO) located near the duodenum papillae is an anatomically and functionally distinct organ, SO motility is controlled and regulated by nerve, hormone and interstitial cells of Cajal. The effect of somatostatin on SO motility is still controversial. This article reviewed effect of somatostatin on human sphincter of oddi motility.

Choledochoscope manometry about different drugs on the Sphincter of Oddi

AIM: To assess the effects of H₂-receptor blocking pharmacon, protease inhibitor, and gastro kinetic agents on the human Sphincter of Oddi (SO) motility by choledochoscope manometry.

METHODS: One hundred and seventy-five patients with T tube installed after cholecystectomy and choledochotomy were assessed by choledochoscope manometry. They were randomly assigned into groups of H₂-receptor blocking pharmacon, protease inhibitor, and gastro kinetic agents. The Sphincter of Oddi basal pressure (SOBP), amplitude (SOCA), frequency of contractions (SOF), duodenal pressure (DP), and common bile duct pressure (CBDP) were scored and analyzed.

RESULTS: SOBP and SOCA were significantly decreased after Cimetidine administration, and no statistical difference was seen in the Famotidine group. In the Gabexate mesilate group, SOBP had decreased significantly. In the Ulinastatin group, SOCA decreased when Ulinastatin was given at the rate of 2500 U/min; when Ulinastatin administration was raised to 5000 U/min, SOBP, SOF and SOCA all experienced a fall. SOBP and SOCA for Domperidone and SOCA for Mosapride groups all decreased distinctly after administration.

CONCLUSION: The regular dosage of Cimetidine showed an inhibitory effect on the motility of SO, while Famotidine had no obvious effects otherwise. Gabnexata mesilate, Ulinastatin and gastro kinetic agents also showed inhibitory effects on the SO motility.

Sphincter of Oddi hypomotility and its relationship with duodenal-biliary reflux, plasma motilin and serum gastrin

AIM: To detect whether patients with a T tube after cholecystectomy and choledochotomy have duodenal-biliary reflux by measuring the radioactivity of Tc99m-labeled diethylene triamine penta-acetic acid (DTPA) in the bile and whether the patients with duodenal-biliary reflux have sphincter of Oddi hypomotility, by measuring the level of plasma and serum gastrin of the patients. Finally to if there is close relationship among sphincter of Oddi hypomotility, duodenal-biliary reflux and gastrointestinal peptides.

METHODS: Forty-five patients with a T tube after cholecystectomy and choledochotomy were divided into reflux group and control group. The level of plasma and serum gastrin of the patients and of 12 healthy volunteers were measured by radioimmunoassay. Thirty-four were selected randomly to undergo choledochoscope manometry. Sphincter of Oddi basal pressure (SOBP), amplitude (SOCA), frequency of contractions (SOF), duration of contractions (SOD), duodenal pressure (DP) and common bile duct pressure (CBDP) were scored and analyzed.

RESULTS: Sixteen (35.6%) patients were detected to have duodenal-biliary reflux. SOBP, SOCA and CBDP in the reflux group were much lower than the control group (t = 5.254, 3.438 and 3.527, P < 0.001). SOD of the reflux group was shorter than the control group (t = 2.049, P < 0.05). The level of serum gastrin and plasma motilin of the reflux group was much lower than the control group (t = -2.230 and -2.235, P < 0.05). There was positive correlation between the level of plasma motilin and SOBP and between the level of serum gastrin and SOBP and CBDP.

CONCLUSION: About 35.9% of the patients with a T tube after cholecystectomy and choledochotomy have duodenal-biliary reflux. Most of them have sphincter of Oddi hypomotility and the decreased level of plasma motilin and serum gastrin. The disorder of gastrointestinal hormone secretion may result in sphincter of Oddi dysfunction. There is a close relationship between sphincter of Oddi hypomotility and duodenal-biliary reflux.

Effects of famotidine and cimetidine on human sphincter of Oddi pressure

AIM: To assess the effects of famotidine and cimetidine at routine dosages on human sphincter of Oddi (SO) motility by choledochoscope manometry.

METHODS: A total of 20 patients with T tubes after cholecytectomy and choledochotomy were randomly divided into famotidine group and cimetidine group (n = 10). The pressure of duodenum (DP), basal pressure of SO (SOBP), contractive amplitude of SO (SOCA), contractive frequency of SO (SOF), contractive duration of SO (SOD) and the pressure of common bile duct (CBDP) before and after drug administration were recorded and analyzed.

RESULTS: The levels of SOCA and SOBP decreased by 25.6% and 57.3% after 10 minutes of cimetidine treatment, and by 25.4% and 19.3% after 20 minutes of cimetidine treatment, respectively. There was significant difference before and after drug administration (P < 0.05). The levels of SOCA and SOBP also decreased after famotidine treatment, but there was no statistical difference. The other indexes had no obvious changes after drug administration.

CONCLUSION: Cimetidine at routine doses can decrease SOBP and SOCA, showing inhibitory effect on the motility of SO, while famotidine had no obvious effect on SO motility.

Changes in potassium ion channel activity of the Oddi's sphincter smooth muscle cells from hypercholesterolemic rabbits

AIM: To study the changes of the contractile responses and potassium ion channel activity in sphincter of Oddi (SO) from rabbits with hypercholesterolemia (HC), and elucidate the underlying mechanisms responsible for these changes.

METHODS: A total of 24 New Zealand female rabbits were divided randomly into control group (n = 12) and HC group (n = 12). SO muscle rings were dissociated from the rabbits in both groups in vitro. The contractile responses of SO to potassium chloride (KCl) was observed firstly. Then the contractile responses evoked by tetraethylammonium (TEA) and 4-aminopyridine (4-AP) were measured. Western blot was employed to examine the expression of potassium ion channels in tissues of HC and control group.

RESULTS: The contractile forces (induced by 60 mmol/L KCl) of SO tissues from HC and control group were 1.23 ± 0.08 and 1.52 ± 0.11 g, respectively. HC group showed a markedly increased contractile response (t = 5.89, P < 0.05). Compared with that in control group, the ratio of contractile responses induced by TEA (3-8 mmol/L) or 4-AP (8-18 mmol/L) to those induced by 60 mmol/L KCl was decreased significantly in HC group (t = 2.72, P < 0.05; t = 4.71, P < 0.05). Western blot indicated that the protein expression of potassium ion channels of SO tissue was significantly reduced in HC group in comparison with that in control group (0.36 ± 0.06 vs 0.84 ± 0.03, t = 3.18, P < 0.05).

CONCLUSION: The contractile response of SO to KCl increases while the activities of BK_Ca and K_V in SO cells decrease in HC rabbits, which might be one of the reasons why SO dysfunction is caused in the condition of HC.

Evaluation of the biliary tract in patients with functional biliary symptoms

The aim of this paper was to describe functional biliary syndromes and methods for evaluation of the biliary tract in these patients. Functional biliary symptoms can be defined as biliary symptoms without demonstrable organic substrate. Two main syndromes exist: Gallbladder dysfunction and sphincter of Oddi dysfunction. The most important investigative tools are cholescintigraphy and endoscopic sphincter of Oddi manometry. In gallbladder dysfunction a scintigraphic gallbladder ejection fraction below 35% can select patients who will benefit from cholecystectomy. Endoscopic sphincter of Oddi manometry is considered the gold standard in sphincter of Oddi dysfunction but recent development in scintigraphic methods is about to change this. Thus, calculation of hilum-to-duodenum transit time and duodenal appearance time on cholescintigraphy have proven useful in these patients. In conclusion, ambient methods can diagnose functional biliary syndromes. However, there are still a number of issues where further knowledge is needed. Probably the next step forward will be in the area of sensory testing and impedance planimetric methods.

Choledochoscopic manometry research of the sphincter of Oddi motility in bile duct stone patients with a T tube after operation

AIM: To study the sphincter of Oddi (SO) motility by choledochoscopic manometry, and to investigate the manometric appearance of sphincter of Oddi disorders and its relationship with bile duct stones.

METHODS: Two hundred and sixteet patients who had a T tube after operation were assessed by choledochoscopic manometry. SO basal pressure (SOBP), amplitude of SO contractions (SOCA), frequency of SO contractions (SOCF), duration of SO contractions (SOCD), duodenal pressure (DP), common bile duct pressure (CBDP), and the percentage of propagate directions were scored and analyzed. The patients were divided into 4 groups according to the levels of sphincter of Oddi basal pressure: group A (sphincter of Oddi hypomotility), group B (normal SOPB), group C (SOBP a little higher than normal) and group D (sphincter of Oddi dysfunction).

RESULTS: The mean SOCA in group A was 62.32 ± 32.13 mmHg, much lower than that in the other three groups (P < 0.01); the mean SOCD in group A was shorter than that in group B and group C (P < 0.01); the mean SOCF in group A had no significant difference from that in group B and group C, but lower than that in group D (P < 0.05); the mean CBDP in group A was 3.89 ± 8.10 mmHg, much lower than that in group D (P < 0.01), but higher than SOBP. The SOCA in group D was 97.02 ± 51.76 mmHg, apparently higher than that in group A (P < 0.01), which was not significantly different from that in group B and group C, but with a tendency to increase; the mean SOCD in group D was shorter than that in group C (P < 0.05), and there was no apparent difference between the other two groups; the mean SOCF in group D was markedly higher than that in the other three groups (P < 0.01 or P < 0.05); the mean CBDP in group D was 10.41 ± 12.37 mmHg, higher than that in group A and B (P < 0.01), but was not statistically different from that in group C; the percentage of retrograde peristalsis in group D (35.73% ± 26.38%) was notably higher than that in group A (20.31% ± 21.96%) and B (22.71% ± 23.86%, P < 0.05).

CONCLUSION: SO dysfunction and hypomotility exist in bile duct stone patients after operation, which can be diagnosed effectively by choledochoscopic manometry. The SO disorders may be associated with the formation or/and recurrence of bile duct stones.

Interplay between nitric oxide and VIP in CCK-8-induced phasic contractile activity in the rabbit sphincter of Oddi

AIM: The sphincter of Oddi (SO) plays an important role in delivery of bile into the duodenum. To establish whether vasoactive intestinal polypeptide (VIP) and nitric oxide (NO) were involved in phasic contractile activity of the rabbit SO stimulated by cholecystokinin-octapeptide (CCK-8).

METHODS: Isolated SO muscle rings were cleaned of fat and mounted horizontally on two small L-shaped hooks one of which was connected to a force transducer for the measurement of isometric tension. The experiments were carried out in a thermostatically controlled (37±0.2 °C) organ bath (5 mL) containing Krebs solution. The organ fluid was gassed with 95% O₂ and 50 mL/L CO₂ to keep the pH at 7.40±0.05. Contractile responses to CCK-8 (1 μmol/L) were evaluated in the presence and absence of N^G-nitro-L-arginine (LNNA), an inhibitor of NO synthase (100 μmol/L), and (p-chloro-D-Phe⁶-Leu¹⁷)-VIP (VIPa, 30 μmol/L), a VIP receptor antagonist.

RESULTS: CCK-8 stimulated the phasic activity of the SO. NO synthase inhibition increased the frequency and amplitude of contractions with a slight increase in developed tension. Pre-incubation with VIPa also attenuated this CCK-8 effect. The combined application of LNNA and VIPa abolished the phasic activity of the muscle rings with a marked increase in tension in response to CCK-8.

CONCLUSION: VIP and NO together contribute to an increase in phasic activity of SO.

Nitroester drug’s effects and their antagonistic effects against morphine on human sphincter of Oddi motility

AIM: To evaluate the effects of nitroester drugs on human sphincter of Oddi (SO) motility and their antagonistic effects against morphine which shows excitatory effect on Oddi’s sphincter motility.

METHODS: The effects of these drugs on SO were evaluated by means of choledochofiberoscopy manometry. A total of 67 patients having T-tubes after cholecystectomy and choledochotomy were involved in the study, they were randomly divided into glyceryl trinitrate (GTN) group, isosorbide dinitrate (ISDN) group, pentaerythritol tetranitrate (PTN) group, morphine associated with GTN group, morphine associated with ISDN group and morphine associated with PTN group. Basal pressure of Oddi’s sphincter (BPOS), amplitude of phasic contractions (SOCA), frequency of phasic contractions (SOF), duration of phasic contractions (SOD), duodenal pressure (DP) and common bile duct pressure (CBDP) were scored and analyzed. Morphine was given intramuscularly while nitroester drugs were applied sublingually.

RESULTS: BPOS and SOCA decreased significantly after administration of ISDN and GTN, BPOS reduced from 10.95±7.49 mmHg to 5.92±4.04 mmHg (P<0.05) evidently after application of PTN. BPOS increased from 7.37±5.58 mmHg to 16.60±13.87 mmHg, SOCA increased from 54.09±38.37 mmHg to 100.70±43.51 mmHg, SOF increased from 7.15±3.20 mmHg to 10.38±2.93 mmHg and CBDP increased 3.75±1.95 mmHg to 10.49±8.21 mmHg (P<0.01) evidently after injection of morphine. After associated application of ISDN and GTN, the four indications above decreased obviously. As for application associated with PTN, SOCA and SOF decreased separately from 100.64±44.99 mmHg to 66.17±35.88 mmHg and from 10.70±2.76 mmHg to 9.04±1.71 mmHg (P<0.05) markedly.

CONCLUSION: The regular dose of GTN, ISDN and PTN showed inhibitory effect on SO motility, morphine showed excitatory effect on SO while GTN, ISDN and PTN could antagonize the effect of morphine. Among the three nitroester drugs, the effect of ISDN on SO was most significant.

Relationship between calcium metabolism and calcium oscillation of Oddi's sphincter in hypercholesterolemic rabbits

AIM: To investigate the effect of hypercholesterolemia on calcium oscillation of acutely separated rabbit Oddi's sphincter muscle cells and to explore its mechanisms.

METHODS: Twenty-four New Zealand female rabbits were divided randomly into control group and HC group (12 rabbits each). Sphincter of Oddi's muscle cells were acutely isolated and cultured. The cells were loaded with Fluo-3/AM, and the changes in calcium oscillation were measured by laser scanning confocal microscopy.

RESULTS: Compared with the control group, the amplitude of the Ca²⁺ oscillation fluorescence intensity was significantly increased in the experimental group (6.11±3.1 vs 3.61±0.94, P<0.05). When treated with nifedipine and EDTA, Ca²⁺ oscillation amplitude in hypercholesterolemic group was decreased by 64% to 2.24±0.72. When treated with thapsigargin, it was decreased by 38% to 3.8±1.9.

CONCLUSION: Calcium metabolic disturbance in Oddi's sphincter muscle cells of hypercholesterolemic rabbits may be caused by the malfunctioned CICR pathway of L-type voltage-dependent calcium channels.