The introduction of a 42 + 4 h work week for surgical residents in Switzerland - a stakeholder analysis.

BACKGROUND: The Swiss national union of residents and attendings (VSAO) has voiced its desire for a transition from the current 48 h work week to a 42 + 4 h work week, in which 42 h be focused on patient care with the remaining 4 h be dedicated solely to training purposes. This could potentially result in a significant decrease in surgical education time. The current study seeks to address the issues involved in its implementation as well as possible compensatory mechanisms. METHODS: This mixed methods study seeks to clearly underline the challenges associated with the implementation of a 42 + 4 h work week. First, the major stakeholders were identified and analysed via umbrella review. Thereafter, a classic stakeholder analysis was performed. Via morphological matrix, possible models for the implementation of a 42 + 4 h work week were developed and evaluated. Finally, representatives from the identified stakeholder groups were interviewed and given the opportunity to provide feedback. RESULTS: A total of 26 articles were identified by the literature search and were used to identify the major stakeholders and issues involved in the implementation of the desired work hour regulation. Overall, these showed conflicting results with regard to the effect decreased working hours would have on surgical training and patient outcomes. In the end, the morphological matrix produced three feasible and desirable models for the implementation of a 42 + 4 h work week. Each included compensatory mechanisms like auxiliary staff, reduction in administrative tasks, and a switch to EPAs. In their interviews, the stakeholders generally supported these solutions. CONCLUSION: Given the increasing emphasis on the importance of a positive work-life balance, it seems inevitable that the next few years will see the introduction of a 42 + 4 h work week in Switzerland. However, it is imperative that every effort be made to preserve the quality of training and patient care for the next generations. This will require the cooperation of all stakeholders in order to find workable solutions.

Mid-term quality of life after gastric band removal and single-stage conversion to gastric bypass: a single-center cohort study.

BACKGROUND: Revision surgeries in patients with failed gastric banding including band removal are increasingly necessary. However, long-term outcomes after band removal alone are unsatisfactory due to weight regain and limited improvement in quality of life. This study aimed to report mid-term quality of life outcomes after gastric band removal and single-stage conversion to Roux-en-Y gastric bypass. METHODS: Data of 108 patients who underwent conversion surgery from 2011 to 2017 were extracted from a prospective database and retrospectively analyzed. During follow-up visits, physical and laboratory data as well as quality of life questionnaires were obtained. RESULTS: Postoperative mean Moorehead score increased significantly after 1 year (1.62 ± 0.86, p < 0.001) and after 5 years (1.55 ± 0.84, p < 0.001) compared to baseline values (0.72 ± 1.1). The mean follow-up time was 53 months. Moorehead scores at 1, 2, and 5 years postoperative were available in 75% (n = 81), 71% (n = 77), and 42% (n = 45) of cases, respectively. Mixed ANOVA analysis showed a significantly superior increase in Moorehead score in males (p = 0.024). No other significant predictors were identified. Lasting BMI reduction (- 4.6 to 33.0 ± 6.7 kg/m2, p < 0.001) and weight loss (- 12.9% (- 13.6 kg), p < 0.001) 5 years after conversion surgery were seen. Postoperative complications occurred in 35% (n = 38) of patients with a re-operation rate of 30.5% (n = 33). CONCLUSION: The current study shows that band removal with single-stage gastric bypass in patients with failed gastric banding leads to a lasting improvement in quality of life and may be the rescue procedure of choice in this setting.

Left-Sided Living Kidney Donation Leads to Transiently Reduced Adrenocortical Responsiveness.

Living kidney donation is safe and established, but can lead to long-term complications such as chronic fatigue. Since the adrenal vein is usually transected during left-sided donor nephrectomy-which is not necessary on the right-we hypothesized that venous congestion might lead to an impairment of adrenal function, offering a possible explanation. In this prospective open label, monocentric cohort study, adrenal function was compared in left- and right-sided living kidney donors. The primary endpoint was plasma cortisol response to low-dose adrenocorticotropic hormone (ACTH) stimulation. Secondary endpoints included plasma renin and ACTH concentration as well as adrenal volume in response to donor nephrectomy. A total of 30 healthy donors-20 left- and 10 right-sided donations-were included. On postoperative day 1, response to low-dose ACTH stimulation was intact, but significantly lower after left-sided donor nephrectomy. After 28 days, adrenal responsiveness to ACTH stimulation did not differ any longer. Magnetic resonance imaging volumetry showed no significant adrenal volume change over 4 weeks, neither after left- nor after right-sided nephrectomy. In conclusion, left-sided living kidney donation entails a transiently reduced adrenocortical responsiveness, which returns to baseline after 28 days.

Delaying surgery to perform CT scans for suspected appendicitis decreases the rate of negative appendectomies without increasing the rate of perforation nor postoperative complications.

PURPOSE: Negative appendectomies are costly and are embedded with unnecessary risks for the patients. A careful indication for surgery seems mandatory even more so, since conservative therapy emerges as a potential alternative to surgery. The aims of this population-based study were to analyze whether radiological examinations for suspected appendicitis decreased the rate of negative appendectomies without increasing the rate of perforation or worsening postoperative outcomes. METHOD: This study is a retrospective analysis of a prospective population-based database. The data collection included preoperative investigations and intraoperative and postoperative outcomes. RESULTS: Based on 2559 patients, the rate of negative appendectomies decreased significantly with the use of CT scan as compared to clinical evaluation only (9.3 vs 5 %, p = 0.019), whereas ultrasonography alone was not able to decrease this rate (9.3 vs 6.2 %, p = 0.074). Delaying surgery for radiological investigation did not increase the rate of perforation (18.1 vs 19.2 %; adjusted odds ratio (OR) 1.01; 0.8-1.3; p = 0.899). Postoperative complications (surgical reintervention, postoperative wound infection, postoperative hematoma, postoperative intra-abdominal abscess, postoperative ileus) were all comparable. CONCLUSION: In this population-based study, CT scan was the only radiological modality that significantly reduced the rate of negative appendectomy. The delay induced by such additional imaging did not increase perforation nor complication rates. Abdominal CT scans for suspected appendicitis should therefore be more frequently used if clinical findings are unconclusive.

Endoluminal vacuum therapy for iatrogenic perforation of the proximal oesophagus.

Iatrogenic perforation of the upper gastrointestinal tract is one of the most serious complications of upper gastrointestinal endoscopy, with high rates of morbidity and mortality. Treatment is challenging because stent placement or surgical repair of the perforation in this area is often impossible. We report on two cases of iatrogenic perforations of the very proximal oesophagus and distal hypopharynx which could be successfully closed by using an endoluminal vacuum sponge treatment for 5 days. Thus, the endoluminal vacuum therapy may be a useful alternative to surgery in such cases of difficultly managable perforations of the upper oesophagus.

The added value of daily diary data in 1- and 3-year prediction of psychopathology and psychotic experiences in individuals at risk for psychosis.

This study aimed to assess whether adding information on psychological experiences derived from a daily diary to baseline cross-sectional data could improve short- (1-year) and long-term (3-years) prediction of psychopathology and positive psychotic experiences (PEs). We used 90-day daily diary data from 96 individuals in early subclinical risk stages for psychosis. Stepwise linear regression models were built for psychopathology and PEs at 1- and 3-years follow-up, adding: (1) baseline questionnaires, (2) the mean and variance of daily psychological experiences, and (3) individual symptom network density. We assessed whether similar results could be achieved with a subset of the data (7-14- and 30-days). The mean and variance of the diary improved model prediction of short- and long-term psychopathology and PEs, compared to prediction based on baseline questionnaires solely. Similar results were achieved with 7-14- and 30-day subsets. Symptom network density did not improve model prediction except for short-term prediction of PEs. Simple metrics, i.e., the mean and variance from 7 to 14 days of daily psychological experiences assessments, can improve short- and long-term prediction of both psychopathology and PEs in individuals in early subclinical stages for psychosis. Diary data could be a valuable addition to clinical risk prediction models for psychopathology development.

Emergency repair and smoking predict recurrence in a large cohort of ventral hernia patients.

PURPOSE: Ventral hernias are frequent and hernia repair is regularly performed by general surgeons. Emergency repair is less frequent and can be challenging. Long-term data comparing outcomes of emergency- vs. elective ventral hernia repair are scarce. METHODS: Consecutive patients undergoing emergency and elective ventral hernia repair at our institution were prospectively entered in our HerniaMed database between August 2013 and February 2020. Patients were contacted after 1 and 5 years to assess long-term complications. Risk factors for emergency repair and hernia recurrence were assessed by univariate and multivariate analysis. RESULTS: We included 1307 patients. Emergency and elective hernia repair were performed in 11% and 89% of patients with 1-year follow-up rates of 94% and 92%. Female gender, BMI > 40 kg/m2, ASA class 3 and 4, large size umbilical herniation (> 4 cm) and epigastric herniation were more frequent in emergency hernia repair. Binary logistic regression analysis identified emergency repair and smoking as predictors of recurrence (Odds ratio: 4.04 and 95% confidence interval: 1.67-14.21, p = 0.004; Odds ratio: 2.94 and 95% confidence interval: 1.33-9.15, p = 0.011). Furthermore, female gender and significant comorbidity (ASA class 3 and 4) were risk factors for emergency repair (Odds ratio: 1.98 and 95% confidence interval: 01.05-3.74, p = 0.034; Odds ratio: 3.54 and 95% confidence interval: 1.79-6.98, p < 0.001). CONCLUSIONS: Emergency repair and smoking predicted hernia recurrence. Females and highly comorbid patients are at increased risk for emergency repair and should be prioritized for early elective hernia repair.

Complications in and performance of double-balloon enteroscopy (DBE): results from a large prospective DBE database in Germany.

BACKGROUND AND STUDY AIMS: Double-balloon enteroscopy (DBE) has been established as an invaluable tool for the diagnosis and treatment of small-bowel diseases. To evaluate complications, procedural data, and diagnostic yield of DBE examinations in Germany the presented database was introduced. METHODS: A prospective database of all DBE examinations in 62 endoscopic centers in Germany was developed using data from a standard questionnaire. Information requested included data on personal information, indications, procedural information, interventions, diagnostic yield, and complications. RESULTS: In total, 2245 DBE examinations in 1765 patients were reported prospectively over a 2-year period. The most frequent indication was overt or occult bleeding in the small intestine and the most frequent intervention was argon plasma coagulation of angiodysplasia. The rate of complete enteroscopy was only 23 %. A clear dependency of indication and diagnostic yield could be documented, ranging widely from a diagnostic yield of 16 % in patients with abdominal pain and 82 % in patients with Peutz-Jeghers syndrome. A total of 27 complications produced a complication rate for all examinations of 1.2 %. Pancreatitis was diagnosed in four cases (0.3 % of oral-route DBE). Perforations occurred in three patients, two of whom had undergone polypectomy in the small bowel (1.5 % of 137 polypectomies). CONCLUSION: DBE is a safe endoscopic technique according to this large prospective database, with a complication rate of 1.2 %. The diagnostic yield of DBE examinations depends upon the quality of indication, and is very low in patients with the single indications of "diarrhea" or "abdominal pain".

Value of combined 6-[18F]fluorodihydroxyphenylalanine PET/CT for imaging of neuroendocrine tumours.

BACKGROUND: Accurate knowledge of tumour presence and location is essential to treat neuroendocrine tumours (NETs). Standard imaging has been hampered by low sensitivity and lack of spatial resolution. This study assessed prospectively the diagnostic value and impact of combined 6-[18F]fluorodihydroxyphenylalanine positron emission tomography-computed tomography (18F-DOPA-PET/CT) in the management of NET. METHODS: 18F-DOPA-PET/CT findings in 61 patients with suspected NET were compared with a composite reference standard including somatostatin receptor scintigraphy (SRS), magnetic resonance imaging, computed tomography, histological examination and clinical follow-up. The impact on clinical management was estimated by calculating the proportion of patients whose treatment changed as a result of 18F-DOPA-PET/CT findings. RESULTS: 18F-DOPA-PET/CT correctly identified 32 of 36 patients with NET. The sensitivity and specificity of 18F-DOPA-PET/CT for the detection of NET were 91 and 96 per cent respectively. Sensitivity using SRS was significantly lower (59 per cent), whereas the specificity was similar (86 per cent). In 16 (26 per cent) of the 61 patients the management was altered as a result of new findings on 18F-DOPA-PET/CT. CONCLUSION: 18F-DOPA-PET/CT yields a high sensitivity and specificity in the detection of NET. The clinical impact was highly relevant as changes in therapy were observed in more than a quarter of the patients.

Laparoscopy for small bowel obstruction: the reason for conversion matters.

BACKGROUND: Although laparoscopy is associated with reduced hospital stay, early recovery, and decreased morbidity compared with open surgery, it is not well established for the treatment of small bowel obstruction (SBO). METHODS: This study analyzed a prospective nationwide database of the Swiss Association of Laparoscopic and Thoracoscopic Surgery. RESULTS: From 1995 to 2006, 537 patients underwent laparoscopy for SBO. Matted adhesions were the main cause of obstruction (62.6%). Intraoperative complications occurred for 9.5% of the patients. Postoperative morbidity was 14% and mortality 0.6%. Within 30 days, 13 patients (2.4%) were readmitted because of early recurrence or complications. The conversion rate was 32.4%. The conversions resulted from inability to visualize the site of obstruction or matted adhesions (53.4%), intraoperative complications (21.3%), and small target incisions for resection (25.3%). Emergency operations were associated with higher conversion rates (43.6% vs 19.8%; p < 0.001) but not with significantly more postoperative complications (15.2% vs 11.9%; p = 0.17). Intraoperative complications and conversion were associated with significantly increased postoperative morbidity (39.2% vs 11.3%; p < 0.001 and 24.7% vs 8.3%; p < 0.001, respectively). Reactive conversion due to intraoperative complications was associated with the highest postoperative complication rate (48.6%). Morbidity for preemptive conversion due to impaired visualization/matted adhesions or a small-target incision was significantly lower (20% and 26.1%; p = 0.02 and p < 0.001, respectively). American Society of Anesthesiology (ASA) scores higher than 2 also were associated with postoperative morbidity (p < 0.001). However, multivariate regression analysis showed that reactive conversion was the only independent risk factor for postoperative morbidity (p < 0.001; odds ratio, 3.97; 95% confidence interval, 1.83-8.64). CONCLUSIONS: Laparoscopic management of SBO is feasible with acceptable morbidity and low mortality but with a considerable conversion rate. Early conversion is recommended to reduce postoperative morbidity.

Long-term follow-up of proximal versus distal laparoscopic gastric bypass for morbid obesity.

BACKGROUND: Laparoscopic gastric bypass is the 'gold standard' for treatment of morbidly obese patients in many centres. There is debate regarding the optimal length for small bowel limbs. This study aimed to determine whether the proximal or distal approach is better. METHODS: Twenty-five patients undergoing primary distal gastric bypass in 2000-2002 were randomly matched for age, sex and preoperative body mass index (BMI) with 25 patients having a primary proximal bypass. All distal operations were performed laparoscopically; one proximal procedure was converted to open surgery. RESULTS: Mean operating time was 170 min for proximal and 242 min for distal bypasses (P = 0.004); median hospital stay was similar in the two groups. There were no deaths and the overall complication rate was similar, as was weight loss at 4 years: BMI decreased from 45.9 to 31.7 kg/m2 for the proximal and from 45.8 to 33.1 kg/m2 for the distal approach. Co-morbidities decreased after surgery in both groups; the prevalence of diabetes, arterial hypertension and dyslipidaemia at all time points was similar in the two groups. CONCLUSION: Proximal and distal laparoscopic gastric bypass operations are feasible and safe, with no differences in weight loss or reduction of co-morbidity in unselected morbidly obese patients.

High secondary failure rate of rebanding after failed gastric banding.

BACKGROUND: Over the last decade, more than 130,000 laparoscopic adjustable gastric bandings (LAGB) have been performed for the treatment of morbid obesity. Nowadays, longer follow-up data are available in the literature and increasing numbers of late complications and treatment failures of gastric banding have been reported. The aim of the present study was the long-term evaluation of two different rescue operations after failed LAGB: conversion to laparoscopic Roux-en-Y bypass (LRYGB) versus laparoscopic gastric rebanding. METHODS: Between January 1997 and November 2002, 74 consecutive patients underwent either laparoscopic gastric rebanding (n = 44) or LRYGB (n = 30) after failed LAGB. There were 14 men and 60 women, with a median age of 42 (23-60) years. The indication for reoperation was an increasing body mass index (BMI) and band-related complications such as pouch dilatation, band slippage, and penetration after LAGB. Rebandings were done by preference during the initial period of the study and LRYGB was the treatment of choice during the latter period. The success of the rescue operation was assessed by postoperative changes in the BMI, improvements of co-morbidities, and the need for further reoperations (secondary failure). The median follow-up was 36 months (range, 24-60 months). RESULTS: Patients who underwent LRYGB had a significantly better weight loss than patients with a rebanding operation (mean -6.1 versus +1.5 BMI points). In addition, the LRYGB patients showed a significantly better control of serum cholesterol during the long term follow-up (-0.6 versus +0.1 mmol/l). Almost half of the patients (45%) in the rebanding group needed a further operative revision, whereas only 20% underwent reoperation after rescue LRYGB. Thus, the secondary failure rate in the rebanding group was significantly higher compared to the bypass group (p = 0.028). CONCLUSIONS: The present long-term study confirms our previous finding that LRYGB is a better treatment than rebanding after failed laparoscopic gastric banding regarding weight loss and treatment of co-morbidities. During the long-term follow-up the reoperation rate due to secondary failure became significantly higher in the rebanding group. We therefore recommend that LRYGB should be preferred as rescue procedure after failed laparoscopic adjustable gastric banding.

A prospective randomized comparison of two instruments for dissection and vessel sealing in laparoscopic colorectal surgery.

BACKGROUND: A newly available, laparoscopic 5-mm bipolar vessel sealing device promises substantial advantages over the 10-mm instrument. This study compared the safety as well as the technical and surgical aspects of these different tools. METHODS: For this study, 30 consecutive patients undergoing laparoscopic left-sided colectomy were prospectively randomized for the 5-mm LigaSure or The 10-mm LigaSure. The patients' demographics were analyzed together with their intraoperative and postoperative parameters, and the instruments were assessed by the surgeons with a standardized questionnaire. RESULTS: The two groups were comparable and demonstrated similar mean operation times, blood losses, and hospital stays. The 5-mm LigaSure was applied in more operation steps and resulted in fewer bleeding episodes and less lens cleaning. Monopolar scissors were used less frequently in the 5-mm group, thus minimizing cauteric lesions and their complications (0 in the 5-mm group vs 2 in the 10-mm group). Overall satisfaction with the 5-mm LigaSure was significantly higher (8.4 +/- 0.18 vs 6.9 +/- 0.41 out of 10; p = 0.002), with significant advantages in terms of dissection capacity, visibility, and handling. CONCLUSION: The 5-mm LigaSure is as secure and fast as the larger 10-mm device and compares favorably in terms of finer dissection as well as trocar flexibility and handling. Therefore, it can be used safely in laparoscopic colorectal surgery.

[Evidential basis in bariatric surgery]. / Was ist "evidence based" in der Adipositaschirurgie?

Bariatric surgery is currently considered the best treatment option for morbid obesity. With the rapid development of laparoscopic techniques, a significant increase in the number bariatric procedures in recent years can be observed. Various surgical techniques to treat morbid obesity have been described, but only few prospective studies compare the different procedures, leading to a lack of evidence for their use. However, from the available literature some general recommendations can be given: (a) preoperative workup in an interdisciplinary team is mandatory, (b) primary bariatric procedures should be performed laparoscopically, and (c) the combination of restrictive and malabsorptive techniques is more efficient than a purely restrictive method, which is also true for the treatment of comorbid diabetes and arterial hypertension. In this paper, we present recent developments in bariatric surgery, with special emphasis on the available evidence for the best treatment of morbidly obese patients.

Type 2 diabetes and acute myocardial infarction. Angiographic findings and results of an invasive therapeutic approach in type 2 diabetic versus nondiabetic patients.

OBJECTIVE: Mortality in diabetic patients with acute myocardial infarction (MI) is high. The significance of the pretreatment coronary status in type 2 diabetic patients with acute MI, as well as the effect of mechanical revascularization using percutaneous transluminal coronary angioplasty (PTCA), has not been established. RESEARCH DESIGN AND METHODS: All patients with type 2 diabetes and acute MI (n = 54) were prospectively enrolled into a study of immediate coronary angiography to guide PTCA of the occluded infarct vessel. Hospital and long-term course were assessed and compared with an unselected control group of nondiabetic patients (n = 358) who were enrolled in the same study. RESULTS: Angiography showed that sites of occlusion and acute coronary flow were similar in both groups. Multivessel disease and shock were more common in type 2 diabetic versus nondiabetic patients: 69 vs. 51% and 21 vs. 10% (P < 0.02), respectively. Direct PTCA was successful in > 90% in both groups. Mortality after 30 days was 13% in type 2 diabetic patients versus 5% in patients without diabetes (P < 0.04). Left ventricular (LV) ejection fraction before discharge was lower in diabetic patients (48 +/- 17 vs. 55 +/- 15%, P < 0.05). Mortality 1 year after discharge was 11 vs. 4% in diabetic versus nondiabetic patients (P < 0.02). Multivariate analysis identified type 2 diabetes as an independent risk factor for acute, but not for late, mortality. CONCLUSIONS: Direct PTCA is safe and effective in type 2 diabetic patients with acute MI. Mortality after 30 days in unselected diabetic patients is < 15% with this approach. Advanced disease and shock contribute to an increased mortality in type 2 diabetic patients with acute MI versus nondiabetic patients.

[Minimally invasive surgery for morbid obesity--evidence or fashion?]. / Morbide Adipositas--Magenband und Magenbypass.

In the last decades surgical treatment for morbid obesity has emerged from being the interest of only few surgeons to a well recognized surgical specialty. This development was promoted by the dramatic increase of prevalence of obesity and the development of laparoscopic surgical techniques. In 1996 the NIH consensus conference stated that bariatric surgery is the most effective therapy to treat obesity and type 2 diabetes, whereas conservative treatment strategies failed in the long-term. Only few studies have compared the different operative strategies. It has been shown that the bypass procedure is better than gastric banding with respect to weight loss and the decrease of comorbidities, but suffers from more short-term morbidity. In recent years, randomized trials have been published comparing laparoscopic with open procedures. These studies show an advantage for the laparoscopic techniques. This paper gives a critical overview on bariatric surgery and summarizes the current literature in this speciality.

Differential sensitivity of rat exocrine and endocrine pancreas to cyclosporine.

The effect of 5, 10, and 20 mg/kg bw cyclosporine on rat endocrine and exocrine pancreatic function was studied. Glucose-dependent insulin secretion from the endocrine pancreas was shown to be significantly impaired 8 days after cyclosporine was given once daily at a dose as low as 5 mg/kg. CCK-8-stimulated amylase and lipase secretion were less sensitive to the noxious effect of cyclosporine being impaired at a dose of 10 mg/kg. Trypsin secretion was shown to be impaired at 20 mg/kg cyclosporine only. Our results demonstrate that cyclosporine causes dose-dependent impairment of both pancreatic endocrine and exocrine functions: the endocrine pancreas being more sensitive to the noxious action than the exocrine pancreas.

Pancreastatin--a mediator in the islet-acinar axis?

Pancreastatin was isolated from porcine pancreas in 1986 and has been shown to inhibit insulin release and exocrine pancreatic secretion in vivo. In the isolated perfused rat pancreas, we investigated its effect on the exocrine pancreas and evaluated its indirect effects mediated via the islet-acinar axis. In the presence of 16.7 mmol/L glucose, 20 pmol/L, 200 pmol/L, and 2 nmol/L pancreastatin reduced insulin release but did not affect exocrine pancreatic secretion stimulated by cholecystokinin (CCK), secretin, or bombesin. Pancreastatin also failed to affect unstimulated exocrine pancreatic secretion. In the presence of 1.7 mmol/L glucose, 200 pmol/L and 2 nmol/L pancreastatin inhibited glucagon release and potentiated CCK-stimulated exocrine pancreatic secretion. Inhibition of glucagon release and augmentation of exocrine pancreatic secretion may be independent phenomena, but they could be linked by the islet-acinar axis. Thus we speculate that a pancreastatin-induced inhibition of glucagon release may indirectly have caused augmentation of exocrine pancreatic secretion.

Endogenous somatostatin possibly controls pancreatic growth: further evidence for feedback regulation.

Specific inhibitors acting upon pancreatic proteinases in the gut can cause pancreatic hypertrophy ('growth'), which is probably mediated through a feedback mechanism utilizing cholecystokinin. We have proposed the involvement of somatostatin, and here test the hypothesis that endogenous somatostatin secreted into pancreatic juice may regulate pancreatic growth. Groups of rats were given the proteinase inhibitor camostate intragastrically for either 3, 7, 14, 28, or 56 days, when they were sacrificed. In some groups the pancreata were weighed and homogenized while in other groups isolated perfused pancreatic organ preparations were performed. Somatostatin was measured in the homogenates, pancreatic juice and portal vein effluents. In camostate-fed animals, pancreatic weights increased to a maximum at 28 days, while pancreatic somatostatin content increased significantly from the third day onwards, and somatostatin secretion into pancreatic juice increased progressively until day 28. In contrast, somatostatin secretion into portal blood remained unchanged from those of untreated controls over the duration of the experiment, and its concentration was lower than in pancreatic juice. These observations provide further evidence that endogenous pancreatic somatostatin may control pancreatic growth in rats.

Stimulatory and inhibitory effects of galanin on exocrine and endocrine rat pancreas.

The influence of the neuropeptide galanin, present in intrapancreatic nerve endings, on the endocrine pancreas is well known. The most potent effect of galanin is inhibition of insulin release. Little is known of its effect on the exocrine pancreas. Whether galanin plays a role in the regulation of exocrine pancreatic secretion and whether this effect is mediated directly on acinar cells or indirectly via the influence on insulin secretion is not clear. In the present study, we investigated these questions using the model of the isolated and arterially perfused rat pancreas with intact exocrine and endocrine secretion. In the presence of 15.8 mM glucose in a modified Krebs-Ringer buffer and during half-maximal stimulation of enzyme secretion with 100 pmol/ml cholecystokinin octapeptide (CCK-8), a dose-response study of 0.001-100 pmol/ml porcine galanin was performed. At concentrations of 0.001 and 0.01 pmol/ml, porcine galanin significantly stimulated insulin release (p < 0.05 and < 0.01, respectively) and also significantly enhanced CCK-8-stimulated amylase secretion (p < 0.05). Doses of 0.1 and 1 pmol/ml galanin resulted in a nonsignificant inhibition of insulin release, while 10 and 100 pmol/ml strongly inhibited the endocrine response (p < 0.001). However, concentration levels of 1-100 pmol/ml galanin did not affect CCK-8-stimulated amylase secretion. Rat galanin, tested at 0.01 and 10 pmol/ml, showed no significant difference from the effects of porcine galanin at the equipotent concentrations. It is concluded that the effect of galanin on exocrine pancreas, like the effect on endocrine functions, tends to be a direct one and that it could exert a modulatory influence on the level of neuronal transmission.