Optimised surgery (so-called TME surgery) and high-resolution MRI in the planning of treatment of rectal carcinoma

BACKGROUND

Since November 1998, we have applied the concept of total mesorectal excision (TME) to rectal carcinoma together with a standardised pathological quality assessment. Participation in the European MERCURY study [The MERCURY Study Group Radiology (in press), 2006] required us to establish the indication for neoadjuvant radiochemotherapy on the basis of an magnetic resonance imaging (MRI) scan. The aim of the present retrospective study is to evaluate the quality of the surgery, the efficacy of the MRI and the oncological outcomes achieved.

MATERIALS AND METHODS

Between November 2001 and October 2005, 68 out of 109 patients with carcinoma of the rectum were submitted to radical surgery in curative intent and 23/68 (34%) were given neoadjuvant therapy. In an interdisciplinary study group, each patient was evaluated pre-operatively and post-operatively using standardised MRI and histopathological methods.

RESULTS

The quality of surgery was established on the basis of the pathological examination of the surgical specimen. The rates of incomplete mesorectal excision, intra-operative tumour cell dissemination and positive circumferential margins were all low at 4%, 7% and 3%, respectively. The effectiveness of MRI proved to be greatest in predicting the tumour status at the circumferential resection margin: in the admittedly limited number of patients it proved possible to correctly predict the tumour status for every patient. The assessment of the anatomic extent of the primary tumour and of the regional lymph node metastasis according to the TNM system, in contrast, was considerably less successful at 73% and 75%, and 37% and 57%, respectively.

CONCLUSION

By applying the TME concept and MRI-based therapy planning, excellent results can be achieved and, at the same time, the number of patients requiring neoadjuvant treatment is considerably reduced.

On the role of gastrin-releasing peptide in meal-stimulated exocrine pancreatic secretion

The contribution of gastrin-releasing peptide (GRP) in the physiologic pancreatic response to a meal is unknown. We therefore investigated whether immunoneutralization of GRP could influence the exocrine pancreatic response to a meal as well as plasma concentrations of the peptide hormones neurotensin (NT) and cholecystokinin (CCK). Modified Herrera fistulas were implanted in five mongrel dogs. After a standard meal, we analyzed plasma NT, CCK, and GRP, and protein and enzyme (amylase, lipase, trypsin) content of exocrine pancreatic juice. An unspecific rabbit immunoglobulin solution was administered intravenously as a control. This experiment was repeated with a specific anti-GRP-immunoglobulin. The i.v. administration of the anti-GRP-antibody significantly inhibited meal-stimulated pancreatic secretion. Integrated protein output decreased from 58.4 to 36.8 g/180 min (p < 0.05), as did amylase (2,102 to 1,145 KU/180 min; p < 0.05), lipase (2,258 to 1,172 KU/180 min; p < 0.05), and trypsin (5,321 to 4,990 U/180 min). Postprandially released NT decreased from 8,271 to 5,825 pmol/180 min (p < 0.05). In contrast, integrated amounts of CCK remained relatively stable with 473 to 611 pmol/180 min. The neuropeptide GRP is one of the biologically important regulatory factors influencing meal-stimulated pancreatic secretion, as well as the postprandial plasma level of the peptide hormone NT in the dog. These mentioned effects of postprandially released GRP seem not to be mediated by CCK in an endocrine manner.

[Unusual diagnosis in recurrent arthritis, erythema nodosum and arrhythmia]

HISTORY AND ADMISSION FINDINGS

A 42-year-old woman, with recurrent arthritis of the large joints and erythema nodosum for 7 years, was admitted because of recent onset of bouts of rapid heart rate. A 2/6 systolic murmur at Erb's point was the only contributory finding on physical examination.

INVESTIGATIONS

The transaminases and gamma-GT were elevated, as were total cholesterol, LDL fraction, IgM, total protein, gamma-globulin and IgM. Antimitochondrial antibodies, especially anti-M2, were positive, while rheumatoid factor and C-reactive protein were negative. ANA, ANCA and antibodies against double-strand DNA were not demonstrated. ENA screening was negative. Abdominal computed tomography showed discrete intrahepatic cholestasis. Liver biopsy revealed chronic destructive cholangitis, i.e. the early stage of primary biliary cirrhosis.

TREATMENT AND COURSE

On treatment with ursodeoxycholic acid (10 mg/kg daily) the patient has remained free of symptoms for 3 years and laboratory tests no longer showed evidence of impaired liver function.

CONCLUSION

Primary biliary cirrhosis should be included in the differential diagnosis of recurrent arthritis and erythema nodosum, as early treatment with ursodeoxycholic acid can favourably influence its course.

Etiology and age have only a limited influence on the course of acute pancreatitis

In a retrospective study of 602 patients with a first attack of acute pancreatitis, it was investigated whether the etiology of the disease and age of the patient are negative factors. There was no significant difference concerning hospital stay, respiratory and renal insufficiency, indication for surgery, or mortality rate among the different etiological groups. However, pancreatic pseudocysts developed significantly more frequently in alcoholics than in patients with other etiologies (p < 0.001 to p = 0.007). There was also no difference concerning hospital stay and respiratory insufficiency among the age groups. The increased incidence of renal insufficiency probably is related to physiological alteration with age, but the indication for dialysis did not increase. Pancreatic pseudocysts were more frequent in patients between 31 and 40 years of age, which was also the peak age group of alcoholics. Indication for surgery was the same for all age subgroups. The increase in mortality rate with age was weakly significant (p = 0.049). For the etiological subgroups, an increase in mortality with age was found only for biliary pancreatitis patients (p = 0.003). It is concluded that etiology and age of the patient have only limited influences on the course of acute pancreatitis.

Morbidity and mortality in 602 patients with acute pancreatitis seen between the years 1980-1994

The course of a first attack of acute pancreatitis was evaluated in a retrospective study of 602 patients, who were admitted between 01.01.1980 and 30.09.1993 to the Centers of Internal Medicine and Surgery of the University of Göttingen (n = 417) and from 16.11.1986 to 30.06.1994 to the Municipal Hospital of Lüneburg (n = 185). Etiology was biliary tract disease in 227 (37.7%), alcohol abuse in 177 (29.4%), unknown in 133 (22.1%), and other causes in 65 (10.8%) patients. Mean hospital stay was 27.9 +/- 24 days (x +/- SD), median 23 days. Pancreatic pseudocysts developed in 14.3% of the patients, and surgical treatment was necessary in 11.1%. Within the first 48 hours, respiratory insufficiency was observed in 63.2% of the 204 patients undergoing arterial blood gas analysis while renal impairment occurred in 32.6% of 602 patients. Artificial ventilation was indicated in 12.5%, and dialysis in 7% of the patients. Mortality rate was 6.1%, correlating significantly with respiratory and renal impairment and procedures in connection with these complications and also with transfers from other hospitals.

[Individual therapeutic procedure in metastatic carcinoid of the small intestine]

Actually, the therapeutic goal in a metastasized carcinoid tumor is rather symptomatic than curative. Here we report the case of a 53 year old woman with a hepatic and pulmonal metastasized carcinoid tumor of the small intestine. We will discuss current therapeutic options and the approach to the individual patient. After treatment with the standard therapeutics Octreotide and Interferon alpha we could achieve a remarkable and persistent remission by applying the rather unusual drug Dacarbacine in this patient. This is an example for the frequently occurring clinical situation in the treatment of patients with rare tumors requiring the application of individually modified therapeutic regimens. Furthermore, the potency of Dacarbacine in the treatment of carcinoid tumors seems to be underestimated up to now.

Effect of a platelet-activating factor antagonist on pancreas perfusion after 24 h of ischemia

Platelet-activating factor (PAF) is a strong mediator of inflammation that is present in many mammalian tissues and cell types. In the pancreas, PAF can be synthesized in acinar cells after stimulation with secretagogues. The present study uses a perfused porcine pancreas model to investigate the role of PAF in pancreatic ischemia and the effect of the PAF antagonist bepafant on pancreas preservation. Pancreata were preserved with or without bepafant, stored for 24 h at 4 degrees C, and then reperfused at 37 degrees C in a perfusion chamber. Reperfusions were significantly improved by the addition of bepafant. This was indicated by a significantly increased arteriovenous volume flow (16.54 +/- 1.88 ml/min versus controls 8.54 +/- 1.31 ml/min; p = 0.0068; bepafant, n = 7; controls, n = 12) and a reduced vascular resistance (p = 0.0068; bepafant, 1.95 +/- 0.22 mm Hg * min/ml versus controls 4.08 +/- 0.56 mm Hg * min/ml). Radioimmunological quantification of PAF in pancreatic tissue revealed that PAF levels remain unchanged during storage in a cold protective solution at 4 degrees C but increase significantly during surgical pancreas preparation under general anesthesia (from 142.1 +/- 21.2 to 368.8 +/- 52.5 pg/g; n = 15; p = 0.0007). The present study shows that bepafant improves pancreas preservation after cold ischemia. The beneficial effect might be explained by antagonizing inflammatory and vasoconstrictory responses to PAF synthesized during surgical pancreas preparation.

Treatment of diarrhea in carcinoid syndrome with ondansetron, tropisetron, and clonidine

A 69-yr-old man with known carcinoid syndrome treated with octreotide and interferon-alpha 2b developed diarrhea, with six to eight watery to semiliquid stools per day. Diminished stool frequency and increased stool consistency were obtained by treatment with the 5-hydroxytryptamine-3 receptor antagonists ondansetron and tropisetron. Successful alleviation of the diarrhea was also observed with the alpha 2-receptor agonist clonidine. These observations indicate that these classes of drugs should be evaluated in a controlled trial in patients with carcinoid-associated diarrhea.

Treatment of metastasized midgut carcinoids with dacarbazine

Seven patients with metastasized midgut carcinoids were treated with intravenous infusion of dacarbazine [dimethyltriazenoimidazole carboxamide (DTIC)] (650 mg/m2) every 4 wk. After 2 wk, white blood cell counts decreased transiently in three patients. No other DTIC-associated side effects occurred. Biochemical markers of disease activity decreased significantly in four patients for 4-20 months (mean duration, 12 months). Size of hepatic metastases was reduced or remained unchanged in six patients for 6-20 months (mean duration, 10 months). Clinical symptoms such as cutaneous flush, diarrhea, abdominal pain, constipation, night sweat, or weight loss improved in six of seven patients. We conclude that DTIC represents a useful therapeutic option in the treatment of advanced and metastasized carcinoid tumors.

[Pancreatic function and quality of life after resection of the head of the pancreas in chronic pancreatitis. A prospective, randomized comparative study after duodenum preserving resection of the head of the pancreas versus Whipple's operation]

Given an indication for surgery in patients with chronic pancreatitis, such as distal common bile duct obstruction, duodenal stenosis, or dilated pancreatic duct with stones and congestion, the surgeon must decide the type of operation to perform. A duodenopancreatectomy, the Whipple procedure, is widely considered to be the gold standard. It is highly effective in relieving pain and eliminating the structural abnormalities noted above. Duodenum-preserving resection of the head of the pancreas (DPRHP) seems to be an attractive alternative to pancreaticoduodenectomy (PD) in the treatment of chronic pancreatitis. In a clinical prospective randomized trial the efficiency of both operative methods was investigated. Between 7/1987 and 12/1993 43 patients were randomly assigned to undergo either a Whipple procedure (n = 21) or DPRHP (n = 22). Data on postoperative course, mortality, and postoperative morbidity were compiled. As concerns long-term results, postoperative hormonal status (insulin, neurotensin, cholecystokinin, gastrin) was checked, basal and stimulated with a standardized meal, using standard hormonal assay kits. All patients with PD survived, whereas one with DPRHP died from peritonitis. Patients with DPRHP had a significant more rapid convalescence (16.5 vs. 21.7 days). The range for postoperative follow-up is from 36 months to 5.5 years. In the DPRHP group 18 patients are in good condition. Two had diabetes and one developed carcinoma. In the PD group one died from hepatic coma, 14 are in good condition and 6 developed diabetes. All gained body weight with an average of 6.4 vs. 4.9 kg, DPRHP vs. PD. A difference between DPRHP and PD was obvious for the postoperative hormonal status. Results are satisfactory in both groups. For patients with DPRHP however, we see a quicker convalescence and a significant benefit as concerns postoperative hormonal status.

Gastrin-releasing peptide and CCK after intraduodenal inhibition of proteases in dogs

The intraduodenal application of a potent protease inhibitor (camostate, 600 mg) causes a significant increase in basal pancreatic secretion in the manner of a negative-feedback mechanism. The integrated protein secretion during the entire study period was 9.9 +/- 1.8 g in 120 min. The iv application of anti-GRP immunoglobulin caused a significant reduction to 5.0 +/- g in 120 min. No significant changes in the plasma concentrations of GRP and CCK were detectable. The increased secretion occurring after the administration of the protease inhibitor could be mediated by neural GRP-dependent mechanisms. These may also be relevant for CCK-dependent factors, which are only briefly mentioned.

Detection of the human glucagon-like peptide 1(7-36) amide receptor on insulinoma-derived cell membranes

125I-glucagon-like peptide 1(7-36)amide was covalently cross-linked to a specific binding protein in human insulinoma cell membranes. A single radiolabeled band at M(r) 63,000 was identified by SDS-PAGE after solubilization of the ligand-binding protein complex. The molecular weight of this apparent GLP-1 receptor in human endocrine pancreatic tissue was of identical size as the GLP-1 receptor on rat insulinoma-derived RINm5F cell membranes. The radiolabeled band was undetectable when 1 microM of unlabeled GLP-1(7-36)amide or of the GLP-1 antagonist exendin(9-39)amide was included in the binding assay. Utilizing isolated poly-A+ RNA from the human insulinoma and a 1,500 bp Eco-RI fragment of the cDNA coding for the rat GLP-1(7-36)amide receptor for Northern blot analysis, a main hybridization signal at about 7 kb was found by Northern blotting. Our data provide the first direct evidence of the existence of GLP-1 receptors in human endocrine pancreatic tissue.

Gabexate mesilate in human acute pancreatitis. German Pancreatitis Study Group

BACKGROUND

A multicenter controlled study was performed to evaluate the effect of high doses of the low molecular weight protease inhibitor gabexate mesilate on mortality and complications associated with moderate and severe acute pancreatitis.

METHODS

Two hundred twenty-three patients from 29 hospitals were entered in the randomized, double-blind trial. Admission to the study was based on strict criteria excluding mild acute pancreatitis. The patients received placebo or 4 g gabexate mesilate per day intravenously for 7 days. All patients were followed up for 90 days after randomization. The analysis was based on 14 complications, including death.

RESULTS

There was no statistical difference in either mortality or complications associated with acute pancreatitis between the placebo and gabexate mesilate groups.

CONCLUSIONS

The results show that gabexate mesilate was not effective in preventing complications and mortality in acute pancreatitis.

Effect of camostate administration for two weeks on experimental pancreatitis in mice and rats

The present study investigates the effect of oral pretreatment with the protease inhibitor camostate on the outcome of pancreatitis in three experimental models. In pancreatitis induced by overstimulation with cholecystokinin (CCK) in rats, pancreatic enzymes and the histological degree of pancreatitis were quantified; in pancreatitis induced by a choline-deficient ethionine-supplemented (CDE) diet in mice, the effect on survival was monitored; and in bile-induced pancreatitis in rats, the effect on survival, pancreatic enzymes, and histology was studied. Feeding of camostate (200 mg/kg/day) for 2 weeks worsened the histological degree of pancreatitis induced by overstimulation with CCK or by injection of taurocholate. The concentration of amylase in the pancreas and in serum was significantly lower after pretreatment with camostate, both in cerulein-induced pancreatitis and in bile-induced pancreatitis, while the concentration of trypsin in the pancreas was significantly increased in the camostate-treated animals. Pretreatment with camostate significantly lowered survival. In pancreatitis induced by a CDE diet, 3 of 20 mice survived the observation period, while 9 of 20 control animals survived (p < 0.05). In taurocholate-induced pancreatitis, 5 of 29 rats were alive after 3 days versus 18 of 30 animals in the control group (p < 0.001). CCK levels were not elevated in camostate-treated rats, when pancreatitis was induced 24 h after finishing camostate feeding. It is concluded that camostate induced pancreatic hypertrophy and increased concentration of proteolytic enzymes aggravate experimental panceatitis and that this is not mediated by increased CCK levels.

The effect of different solutions for organ preservation on immediate postischemic pancreatic function in vitro

The present study compares the effect of organ preservation with Euro-Collins solution, cardioplegic histidine-tryptophan-ketoglutarate solution, and University of Wisconsin solution on immediate pancreatic function after cold storage at 4 degrees C for 24 hr. Postischemic organ quality of a porcine pancreas preparation was tested by quantification of physiological and biomedical parameters in a one-line reperfusion system. During reperfusion with a constant arterial pressure the arteriovenous flow rate was significantly higher for HTK (5.7 +/- 0.91 ml/min, n = 8; P < 0.05 vs. EC) and UW (7.4 +/- 0.81 ml/min, n = 8; P < 0.05 vs. EC) than for EC (3.0 +/- 0.26 ml/min, n = 6). The lowest lactate content in the reperfusate was found after HTK protection (HTK, 64.0 +/- 7.2 mumol/50 ml, n = 8; versus EC, 114.2 +/- 1.7 mumol/50 ml, n = 6, P < 0.001; versus UW, 148.0 +/- 28.6 mumol/50 ml, n = 8, P < 0.05). Amylase in the venous effluent was significantly lower (P < 0.05) for HTK or UW protection than for EC (HTK, 189 +/- 72.6 U/ml; UW, 188 +/- 39.4 U/ml; EC, 416 +/- 71.7 U/ml). Oxygen consumption during reperfusion was significantly higher for HTK (2.15 +/- 0.22 microliters/g/min, P < 0.001) and UW (1.80 +/- 0.52 microliters/g/min, P < 0.05) than for EC (0.47 +/- 0.13 microliters/g/min). We conclude that immediate postischemic organ quality and pancreatic function after protection with HTK is not inferior to preservation with UW.

Influence of a platelet-activating factor antagonist on severe pancreatitis in two experimental models

This study investigates the role of platelet-activating factor (PAF) in experimental pancreatitis. The concentration of PAF quantified in ascites of bile-induced pancreatitis by radioimmunoassay (RIA) ranged from 3.67 +/- 0.39 pmol/mL 2 h to 0.954 +/- 0.39 pmol/mL 10 h after injection of taurocholate. Administration of a potent PAF antagonist, WEB-2170, prior to injection of taurocholate prolonged mean survival time in rats receiving i.v. camostate and albumin (46.4 h, n = 15, vs controls 38.3 h, n = 13). However, the survival rate after 72 h was not improved. The histologically estimated severity of pancreatitis and pancreatic enzymes in blood, tissue, or ascites was not affected. WEB-2170 had no effect on survival when injected simultaneously with taurocholate into the pancreatic duct or given i.v. after induction of pancreatitis (1, 0.1, or 0.01 mg/kg WEB-2170 vs controls). Subcutaneous injection of 10 mg/kg WEB-2170 also did not improve survival in pancreatitis induced by choline-deficient, ethionine-supplemented diet in mice. It is concluded that administration of a PAF antagonist after the onset of severe experimental pancreatitis does not influence its outcome, although activation of PAF may play a role in the pathogenesis of pancreatitis.

Influence of the CCK-antagonist loxiglumide on bile-induced experimental pancreatitis

The present study investigates the effect of CCK-receptor blockade on taurocholate-induced pancreatitis in rats using the potent antagonist loxiglumide. Intraperitoneal administration (50 mg/kg) of loxiglumide began 3 h before, or 10 min or 3 h after induction of pancreatitis. Mean survival times of the experimental groups were 31.2, 23.6, and 20.5 h, respectively, compared to 18.2 h for controls. Survival for 24 h after induction of pancreatitis was significantly improved when the antagonist was given 3 h before, but not in the time periods after induction. After 72 h, survival time was not significantly altered in any of the groups. Furthermore, amylase and lipase levels quantified 10 h after induction of pancreatitis in ascites, blood, or tissue did not indicate a significant difference, nor was improvement in survival seen when the CCK-antagonist was tested in rats receiving a basal treatment with intravenous volume substitution, peritoneal lavage, and protease inhibition. We conclude that CCK-receptor blockade does not improve the final outcome of bile-induced pancreatitis in the rat, even if treatment is started before induction of pancreatitis.

Treatment of gastrointestinal endocrine tumours with interferon-alpha and octreotide

This paper reports on the results of two controlled therapeutic trials on patients with endocrine tumours of the gastrointestinal tract. Seventeen patients were treated up to 18 months with recombinant interferon-alpha 2c (2 x 10(6) IU/m2 s.c. daily) and 16 patients are treated in an ongoing study with octreotide (3 x 200 micrograms daily). Objective response (greater than 50% reduction of hormone secretion) was observed in one of 15 evaluable patients on IFN-alpha and in 12 of 16 patients on octreotide. Reduction of tumour size was not observed in these two trials. However, the majority of patients had stable tumour size during IFN-alpha and octreotide treatment despite progressive disease before. Subjective improvement due to reduction of symptoms such as flushing, diarrhea, and dermatitis was significantly more frequent after octreotide than after IFN-alpha. Of five endocrine tumour patients with progressive disease on IFN-alpha, three responded to subsequent treatment with octreotide while one had stable disease and one progressed. Two cases are reported from the authors' series of patients treated with octreotide before start of these trials. Complete remission of the tumour by low-dose (2 x 100 micrograms daily) octreotide was observed in one carcinoid patient. This remission has now lasted for four years. In one patient with liver metastasis of a VIPoma, who had become resistant to streptozotocin, his watery diarrhoea is now completely controlled with 100 micrograms octreotide s.c. every second day.

Antral Helicobacter pylori-like organisms in different states of gastric acid secretion

The frequency of Helicobacter pylori (H.p.) infestation in antral mucosa and the presence of gastritis were investigated in different states of gastric acid secretion. Biopsies were stained by the Warthin-Starry technique and hematoxylin-eosin. Antral H.p. was found in similar frequencies in Zollinger-Ellison syndrome (n = 17; profound acid hypersecretion, associated with duodenal ulcer disease in most cases) and the same number of age-matched controls (35% in each group) whereas H.p. could be detected in 31 out of 33 duodenal ulcer patients (94%). The incidence of H.p. infestation in H2-blocker refractory reflux oesophagitis was low (24%). Treatment of peptic lesions with omeprazole (drug-induced hypochlorhydria) led to a reduction or disappearance of H.p. in 7 out of 10 H.p.-positive patients whereas none of 19 primarily H.p.-negative patients became infected with H.p. during prolonged omeprazole therapy. It is concluded that (1) development of duodenal ulcers (as in gastrinomas) does not necessarily require H.p., and (2) at least in some patients H.p. is reduced in antral mucosa by omeprazole.

Camostate (FOY-305) improves the therapeutic effect of peritoneal lavage on taurocholate induced pancreatitis

The effect of peritoneal lavage with the addition of camostate to the lavage fluid on the outcome of taurocholate pancreatitis in rats was studied. Camostate is a low molecular weight protease inhibitor which has been developed recently. Peritoneal lavage was performed for 12 hours and camostate was added to the lavage fluid in five concentrations. At 0.1 mg/ml the survival rate increased significantly (11 of 20 v controls 4 of 20, p less than 0.05); the maximal effect was observed at 0.2 mg/ml, and no effect was seen at 0.01 and 0.05 mg/ml. Adverse effects occurred at 0.5 mg/ml. The addition of 0.1 mg/ml camostate significantly reduced the acidosis in arterial blood: mean (SD) pH 7.30 (0.035) v controls 7.23 (0.054) (n = 9, p less than 0.01) and arterial base excess: -15.4 (1.26) mmol/l v controls: -17.4 (2.51) mmol/l (n = 9, p less than 0.05). There was no difference, however, in plasma amylase activity and in the histological degree of specific tissue damage to the pancreas. A combination of intravenous camostate and lavage with the addition of camostate to the lavage fluid yielded a significantly improved survival compared with treatment with intravenous camostate alone (10 out of 16 animals v intravenous camostate alone, two out of 16, p greater than 0.01). We conclude that lavage with camostate significantly improves the prognosis of severe necrotising pancreatitis in rats.

Evaluation of a euglycaemic clamp procedure as a diagnostic test in insulinoma patients

In 15 patients with insulinoma, six patients after successful removal of this tumour, two patients with previous pancreas resection because of hypoglycaemia elsewhere, and 10 control subjects, the diagnostic usefulness of euglycaemic clamp procedures (without exogenous insulin) was assessed in comparison with prolonged starvation. Only insulinoma patients developed sustained hypoglycaemia (less than or equal to 2.3 mmol l-1) within 2-44 h without caloric intake, because of inappropriately elevated immunoreactive insulin (IR-insulin) concentrations. IR-proinsulin values were elevated in most (7 out of 10), but not in all insulinoma patients. The steady-state glucose infusion rate necessary to maintain a stable plasma glucose concentration of 4.4-5.0 mmol l-1 was significantly (P less than or equal to 0.001) higher in insulinoma patients (2.5 +/- 0.6 mg kg-1 min-1) than in pancreas resected patients (0.6 +/- 0.2 mg kg-1 min-1), or in control subjects (0.5 +/- 0.1 mg kg-1 min-1). Due to a considerable degree of overlap, sensitivity (0.44) and specificity (0.95) were too low for such a procedure to qualify as a diagnostic test. There was no correlation of glucose infusion rates to IR-insulin values (r = 0.024, P = 0.461). One reason for this was the development of insulin resistance in some, but not in all insulinoma patients. When, in analogy to insulin/glucose ratios, a diagnostic index was derived by multiplying the steady state glucose infusion rate by the steady state IR-insulin concentration, the diagnostic accuracy was greatly increased (sensitivity and specificity 0.94, respectively), but still lower than that of 'amended' insulin/glucose ratios in fasting plasma or at the time of discontinuation of prolonged fasts (1.00). Somatostatin infusions inhibited insulin secretion (IR-C-peptide plasma concentrations) by 52-88% in subjects without insulinoma and in those insulinoma patients whose tumour cells ultrastructurally contained plenty of normal secretory granules, and to a lesser degree when only abnormal or virtually no secretory granules were present, i.e. in more de-differentiated tumours. In contrast to this significant (P = 0.036) association, malignancy, i.e. the presence of metastases, could not be predicted from whether or not insulin secretion was resistant to the inhibitory action of somatostatin. In conclusion, euglycaemic clamp experiments are less reliable for detecting or excluding a functioning insulinoma than the relation of glucose and insulin values during starvation. The inhibition of insulin secretion by somatostatin depends on the presence of normal beta-granules, and does not distinguish adenomas from carcinomas.

Acute and chronic effects of cyclosporine A on pancreatic polyamine metabolism and pancreatic adaptation

The present study was designed to investigate the effects of acute and chronic application of the immunosuppressive agent cyclosporine A (CsA) on pancreatic polyamine metabolism as well as pancreatic growth of rats in vivo. Seven to ten animals per group were treated with either the synthetic trypsin inhibitor camostate (FOY-305, 200 mg/kg b.wt. p.o. twice a day), CsA (10 mg/kg b.wt. p.o. once a day), camostate plus CsA, or oil as control, and animals were killed after 8 h, 1, 5 and 14 days. Feeding of camostate resulted in a significant increase of the measured parameters in the following time-course: cholecystokinin (CCK), 8 h; ornithine decarboxylase (ODC), 8 h: putrescine, 8 h; S-adenosylmethionine decarboxylase (SAM-DC), 1 day; pancreatic weight, 1 day; protein content, 5 days; spermidine, 5 days; RNA, 5 days; and DNA, 14 days. Simultaneous treatment with CsA resulted in a significant inhibition of camostate-induced increases in ODC, SAM-DC as well as putrescine and spermidine and furthermore caused a nearly complete inhibition of the increase of all trophic parameters, while CCK plasma levels were not altered. Counterregulatory mechanisms to maintain the intracellular polyamine pool as known after application of specific inhibitors of enzymes of the polyamine metabolism (i.e. DFMO) were not observed. Therefore we conclude that CsA does not directly interact with the polyamine metabolism, but rather with the second messenger system or any other intracellular mechanism, that is activated after stimulation with CCK before the polyamine metabolism is induced.

Impairment of stimulated insulin release from the isolated perfused rat pancreas by cyclosporine pretreatment

Cyclosporine was fed to male Wistar rats in a dose of 5, 10, or 50 mg/kg b.wt. for 7 days, and the effect on insulin secretion from the isolated perfused pancreas was investigated. Dose-dependently plasma insulin and pancreatic insulin content decreased while whole-blood CsA levels increased. An increase in blood glucose was only observed after feeding 50 mg/kg b.wt. CsA resulting in whole-blood CsA levels of 7735 ng/ml. Glucose (20 mM)-stimulated total insulin secretion (ng/50 min) was not affected during feeding 5 mg/kg b.wt. CsA, but was significantly reduced after feeding 10 or 50 mg/kg b.wt. CsA. The biphasic insulin secretion was reduced after 5 mg/kg b.wt. during the initial peak (0-10 min) but not during the second peak (10-50 min), whereas after 10 or 50 mg/kg b.wt. CsA both peaks were markedly reduced. The arginine (20 mM) and the arginine (20 mM)-plus-glucose (20 mM) stimulated insulin secretion was less affected after feeding 10 mg/kg b.wt. CsA than after stimulation with glucose (20 mM) alone. The addition of CsA to the perfusate did not influence glucose-stimulated insulin release from normal rat pancreas. Our results demonstrate a toxic effect of CsA on the pancreatic beta cell that is dose dependent and possibly influences both insulin secretion and biosynthesis.

Dose-dependent inhibition by cyclosporine A of the induction of pancreatic ornithine decarboxylase (ODC) in rats

The effect of cyclosporine A (CsA) and alpha-difluoromethylornithine (DFMO) on the camostate-induced increase in pancreatic ornithine decarboxylase (ODC) activity and polyamine biosynthesis has been studied in vivo. Six hours after application of the synthetic trypsin inhibitor camostate (200 mg/kg b wt orally) pancreatic ODC activity increased about 140-fold and putrescine concentration about ninefold. CsA inhibited the elevation of both parameters in a dose-dependent manner. CsA pretreatment for 3 d with doses of 7.5, 10.0, and 12.5 mg/kg b wt orally once a day and consecutive CsA blood levels 24 h after the last CsA application of 751 +/- 62, 968 +/- 70, and 1,395 +/- 79 ng/mL, respectively, resulted in a complete inhibition of the camostate-stimulated increase in pancreatic ODC activity and putrescine concentration in vivo. DFMO (2% in drinking water and additionally 300 mg/kg b wt intraperitoneally at 8 AM, 12 noon, and 4 PM) inhibited the increase in both, ODC activity, and putrescine, significantly in an equipotent degree as 2.5 mg CsA/kg b wt, whereas higher doses of CsA proved to be more effective than DFMO in the chosen subtoxic dose. In all cases, no significant changes in pancreatic spermidine and spermine concentration, DNA and protein content, or pancreatic and body weight were observed. It is concluded that CsA in doses used for immunosuppression in clinical practice is a very potent and more effective inhibitor of ODC activity and polyamine synthesis in vivo than DFMO. This ODC inhibitory effect of CsA is a further detail to elucidate the up to now incompletely understood mechanisms of action of this immunosuppressive agent.

The effect of cyclosporin A on rat pancreatic B-cell: interaction with the calcium-antagonist diltiazem

Cyclosporin A (CyA) was fed to male Wistar rats in a dose of 5, 10 or 50 mg/kg b.wt. for 7 days. In another experimental procedure 10 mg/kg b.wt. CyA was given for 7 days combined with Diltiazem (DIL) 6.25 mg/kg b.wt. once daily ip. Glucose stimulated insulin secretion from the isolated perfused pancreas was investigated in these animals. Total insulin secretion (ng/50 min) was not affected after feeding 5 mg/kg b.wt. CyA, but was significantly decreased with 10 and 50 mg/kg b.wt. CyA. The biphasic insulin secretion was reduced after 5 mg/kg b.wt. CyA during the initial peak (0-10 min) but not during the second peak (10-50 min), whereas after 10 and 50 mg/kg b.wt. CyA both peaks nearly reached base-line levels. DIL markedly increased the initial peak (0-10 min) after feeding CyA 10 mg/kg b.wt., whereas the second peak was not affected. Our results demonstrate a toxic effect of CyA on the pancreatic B-cell, which might be partly abolished by calcium-antagonists.

Effect of a long-acting somatostatin analogue (octreotide) on circulating tachykinins and the pentagastrin-induced carcinoid flush

Cutaneous flushing was provoked in seven patients with metastatic carcinoid tumours and the carcinoid syndrome by an intravenous injection of pentagastrin (0.6 micrograms.kg-1 body weight). The patients were studied before and 1 h after a subcutaneous injection of the long-acting somatostatin analogue octreotide 50 micrograms (Sandostatin). The severity of the carcinoid flush in all the patients was reduced by administration of the analogue. The rise in facial temperature was 1.3 (0.3) degree C before and 0.8 (0.2) degree C after octreotide. Six patients responded to pentagastrin with a rise in the circulating neurokinin A-like immunoreactivity (NKA-LI) and five patients with a rise in circulating substance P-like immunoreactivity (SP-LI). No cutaneous flushing or rise in tachykinin concentration was observed in healthy subjects (n = 6) after injection of pentagastrin. The rise in NKA-LI in the patients was decreased by 61 (14)% and the rise in SP-LI by 54 (13)% after octreotide. Although flushing still occurred, the tachykinin response in two patients was completely abolished. The data demonstrate that the release of tachykinins from carcinoid tumours during pentagastrin-induced flushing is subject to partial inhibition by octreotide. However, the occurrence of a flush in some patients in the absence of a detectable rise in circulating tachykinins indicates that the latter peptides cannot be the sole causative agent of the carcinoid flush.

Influence of CCK antagonist L-364,718, pancreastatin (33-49) and a somatostatin analogue on camostate-induced rat pancreatic hypertrophy

Since endogenous cholecystokinin (CCK) is released after oral administration of camostate, it has been suggested that camostate-induced pancreatic growth is mediated via circulating CCK. To test this concept, we investigated the effects of three potentially inhibitory substances on rat pancreatic hypertrophy caused by feeding of camostate over 2 weeks: (1) L-364,718, the novel specific highly potent nonpeptide CCK receptor antagonist, (2) octreotide (SMS 201-995), a potent long-lasting somatostatin analogue and (3) pancreastatin (33-49), the biologically active C-terminal fragment of the novel gastrointestinal peptide pancreastatin. Camostate feeding (200 mg/kg) once daily for 14 days induced a significant increase in pancreatic weight, total protein, trypsinogen and polyamine levels, whereas total amylase content was substantially diminished. Simultaneous oral or subcutaneous treatment with L-364,718 (0.3 mg/kg twice daily) completely suppressed all trophic effects of camostate. Octreotide (25 micrograms/kg twice daily s.c.) and pancreastatin (33-49) (10 micrograms/kg twice daily s.c.) did not change any trophic parameter. In case of octreotide it could be shown that two daily injections only partially suppressed elevated CCK levels. Pancreatic DNA and putrescine levels were slightly reduced in rats receiving the CCK antagonist alone. These results demonstrate that camostate-induced pancreatic hypertrophy in rats is caused by the release of endogenous CCK which may contribute to the maintenance of normal pancreatic DNA and putrescine concentrations.

Quantitative studies of gastric endocrine cells in patients receiving long-term treatment with omeprazole

A total of 36 patients with chronic gastric or oesophageal peptic ulceration (including 6 with antrectomy), resistant to high-dose ranitidine treatment for at least 3 months, were successfully treated with omeprazole 20-60 mg/day, for periods up to 3 years. Fasting serum gastrin levels were monitored at regular intervals during therapy and multiple gastric mucosal biopsies were taken during gastroscopy every 3-6 months. Gastrin levels increased significantly during the first 6 months of therapy from a mean of 81.5 to 206 pg/ml; a slight decrease was observed thereafter. There was no significant increase in the volume density of argyrophilic cells in the oxyntic mucosa. No clusters of endocrine cells were found in the oxyntic mucosa and no change of G-cell volume density occurred in the antral mucosa under therapy. Omeprazole therapy did not result in any changes in gastrin levels or oxyntic argyrophilic cells in the antrectomized patients. It is concluded that the moderate hypergastrinaemia observed during long-term omeprazole treatment in man does not induce hyperplasia of argyrophilic cells in the oxyntic mucosa.

Diltiazem inhibition of glucose-induced insulin secretion from the isolated perfused rat pancreas

The effect of the calcium channel blocker diltiazem on stimulated insulin release from the isolated perfused rat pancreas was studied. Rats were treated for seven days with three dosages of diltiazem. Both phases of glucose-stimulated insulin secretion from the isolated perfused rat pancreas were diminished dose dependently.

[Treatment of gastrointestinal neuroendocrine tumors with the somatostatin analog octreotide (Sandostatin)]

Somatostatin, a 14 amino acid peptide hormone, is a potent inhibitor for secretion of gastrointestinal hormones from endocrine cells. The clinical use of somatostatin for treatment of endocrine gastrointestinal tumours was limited due to its short half-life (2-3 min). Octreotide (Sandostatin), a long-acting somatostatin analogue, has been developed for subcutaneous use with an elimination half-life of about 45 min. This offers a new way of long-term treatment for patients with endocrine gastrointestinal tumours. The effect of octreotide in various forms of these diseases and its importance for the possible inhibition of tumour growth are described.

Circulating bradykinin-like immunoreactivity and the pentagastrin-induced carcinoid flush

Bradykinin and structurally related peptides are potent vasodilators and a role for these kinins in the aetiology of the carcinoid flush has been proposed. Using an antiserum directed against the COOH-terminal region of bradykinin in radioimmunoassay, the concentrations of bradykinin-like immunoreactivity in extracts of peripheral blood were compared in patients with carcinoid syndrome (n = 11) and healthy subjects (n = 6). In the fasted state, the concentrations of bradykinin-like immunoreactivity in the patients (10 +/- 5 ng/l) were not significantly different from the concentrations in healthy subjects (6 +/- 3 ng/l). An intravenous injection of pentagastrin (0.6 micrograms/kg) provoked a flush of differing degrees of severity in all patients. In four patients, the flush was concurrent with large rises (277-, 26-, 11- and 10-fold over mean basal values) in bradykinin-like immunoreactivity that was resolved by high performance liquid chromatography into lysyl-bradykinin and bradykinin (approximate ratio 1:2). In two patients, small rises in immunoreactivity (2.4- and 1.7-fold) occurred after the flush and in the remaining five patients no rise in bradykinin-like immunoreactivity was measured. In the healthy subjects, the pentagastrin injection did not provoke a flush and no rises in bradykinin-like immunoreactivity were observed. The data support earlier results obtained using bioassays that the carcinoid flush in some patients is associated with the appearance in blood of bradykinin-related peptides. It has been shown, however, that these kinins cannot be the sole causative agent of the flush. It is suggested, therefore, that the aetiology of the flush is probably multi-factorial.

Long-term omeprazole treatment in man: effects on gastric endocrine cell populations

36 patients with chronic gastric or oesophageal peptic ulceration (including 6 with antrectomy), resistant to high-dose ranitidine treatment for at least 3 months, were successfully treated with 40-60 mg of omeprazole daily for periods between 1 and 2 years. Fasting serum gastrin levels were monitored at regular intervals during therapy and multiple gastric mucosal biopsies were taken during gastroscopy every 3-6 months. Gastrin levels increased significantly during the first 6 months of therapy from a medium level of 81.5 to 206 pg/ml, a slight decrease was seen thereafter. In 10 patients investigated before the start of the treatment and after 1 and 2 years, the volume density of argyrophilic cells in the oxyntic mucosa increased from 0.43 +/- 0.08 to 0.91 +/- 0.14% during the first year; this change was statistically significant. No further increase was observed thereafter. No such difference could be demonstrated between a larger group of 18 patients investigated before and after 1 year of treatment with omeprazole (0.806 +/- 0.1 vs. 0.93 +/- 0.08%) and between a larger group of 22 untreated patients and 17 patients treated for 17-24 months with omeprazole (0.73 +/- 0.1 vs. 0.86 +/- 0.09%). The volume density of argyrophilic cells found in 8 patients with gastrinoma amounted to 1.37 +/- 0.22%. No clusters of endocrine cells were found in omeprazole-treated patients. The D cell volume density in the antral mucosa decreased significantly during the first months of treatment, but steadily increased thereafter to reach pretreatment values after 17 months. There was no change in G cell volume density under therapy. No changes in gastrin levels or oxyntic argyrophilic cells were observed in the antrectomized patients. It is concluded that the hyperplasia of argyrophilic cells observed in some patients during long-term omeprazole treatment is mediated by hypergastrinaemia.

Xenopsin- and neurotensin-like peptides in gastric juice from patients with duodenal ulcers

Using an anti-serum directed against the COOH-terminal region of neurotensin and an anti-serum raised xenopsin in radioimmunoassays, the presence of neurotensin- and xenopsin-like immunoreactivity in Sep-pak extracts of human gastric juice was demonstrated. An anti-serum directed against the NH2-terminal to central residues of neurotensin and an anti-serum directed against a conformation, present only in the intact peptide, did not detect immunoreactivity in the juice. Infusions of pentagastrin at doses of 0.75 micrograms kg-1 h-1 and 1.5 micrograms kg-1 h-1 resulted in significant (P less than 0.05) increases in the total amount of xenopsin-like, but not neurotensin-like, immunoreactivity released in the juice compared with basal release. No significant differences in the release of xenopsin- or neurotensin-like immunoreactive were observed between patients with selective proximal vagotomy and patients without operation. Analysis by gel permeation chromatography and high performance liquid chromatography demonstrated that both the neurotensin- and xenopsin-like immunoreactivity was heterogeneous and an increase in molecular complexity on pentagastrin-stimulation was observed. As both neurotensin and xenopsin inhibit gastric exocrine activity, the presence of immunochemically related substances in gastric juice may have physiological relevance.

Circulating tachykinins (substance P, neurokinin A, neuropeptide K) and the carcinoid flush

Antisera of defined regional specificity have been used to measure the concentration of substance P-like immunoreactivity (SP-LI) and neurokinin A-like immunoreactivity (NKA-LI) during a meal-induced flush in 10 patients with metastatic carcinoid tumours. Although all patients flushed, NKA-LI levels in five patients and SP-LI in six patients were not elevated relative to healthy subjects (NKA-LI, less than 3 pg/ml; SP-LI, less than 10 pg/ml) both in the fasted state and after food. In the patients with elevated basal plasma tachykinin levels, increases in NKA-LI and SP-LI after food were erratic and did not correspond to a defined digestive phase or the occurrence of the flush. Chromatographic analysis of plasma demonstrated the presence of neuropeptide K and neurokinin A, and the detection of COOH-terminal fragments of substance P is consistent with the higher levels of circulating SP-LI measured with a COOH-terminally directed antiserum compared with an NH2-terminally directed antiserum. Subcutaneous injection of the somatostatin analogue SMS 201-995 (50 micrograms) alleviated symptoms of flush in two of three patients but only partially suppressed NKA-LI and SP-LI concentrations. It is concluded that circulating tachykinins cannot be solely responsible for the meal-induced carcinoid flush.

Serotonin release into blood after food and pentagastrin. Studies in healthy subjects and in patients with metastatic carcinoid tumors

The effect of a 550-kcal mixed meal and of an intravenous injection of pentagastrin (0.06 microgram/kg body wt) upon peripheral blood serotonin concentrations has been compared in 10 carcinoid patients with hepatic metastases and healthy subjects. The fasting concentrations of blood serotonin in the patients (range 790-4500 ng/ml) were elevated compared with healthy subjects (range 71-310 ng/ml; n = 15). Urinary output of 5-hydroxyindole acetic acid was elevated in 8 patients but was in the healthy range for 2 patients. The healthy subjects (n = 9) responded to food with an increase in blood serotonin (maximum rise over mean basal of 32% +/- 4%) that was significant at 60, 75, 90, and 105 min postcibal. All carcinoid patients responded to food with a comparable (25% +/- 11% over basal) rise in serotonin but the pattern of release was erratic. All patients with tumor metastases exhibited symptoms of the carcinoid flush after eating, but there was no correlation between occurrence and severity of the flush and occurrence and magnitude of the rise in serotonin. Intravenous pentagastrin evoked a flush in all carcinoid patients, but there was no significant increase in peripheral blood serotonin either in the patients or in healthy subjects.

Effect of short- and long-term feeding of omeprazole on rat gastric endocrine cells

Rats were tube-fed with omeprazole (40 mumol/kg body weight twice daily) for 30 and 60 days. As a result, fasting plasma gastrin levels were significantly elevated, while plasma somatostatin levels remained normal. Gastrin concentrations in the antral mucosa were unchanged after 30 days, but significantly elevated after 60 days. The relative stomach weight and the area of the antral and oxyntic mucosa increased significantly; however, the oxyntic mucosa thickness and the volume density of the parietal cells did not increase. Highly significant changes occurred in the endocrine cells of the antrum and corpus. The volume density of the argyrophilic (Grimelius technique) cells of the oxyntic mucosa increased time-dependently, and so did the volume density of the antral G cells, while the volume density of the antral D cells decreased. This resulted in a remarkable increase in the G/D cell ratio. All functional and morphological changes are reversed 42 days after omeprazole feeding for 60 days. The findings in the endocrine cells of the antral mucosa are explained by the omeprazole-induced permanent elevation of the intragastric pH and in the endocrine cells of the oxyntic mucosa by the following hypergastrinaemia.

Reduced incretin effect in type 2 (non-insulin-dependent) diabetes

Integrated incremental immunoreactive insulin and connecting peptide responses to an oral glucose load of 50 g and an "isoglycaemic" intravenous glucose infusion, respectively, were measured in 14 Type 2 (non-insulin-dependent) diabetic patients and 8 age- and weight-matched metabolically healthy control subjects. Differences between responses to oral and intravenous glucose administration are attributed to factors other than glucose itself (incretin effect). Despite higher glucose increases, immunoreactive insulin and connecting peptide responses after oral glucose were delayed in diabetic patients. Integrated responses were not significantly different between both groups. However, during "isoglycaemic" intravenous infusion, insulin and connecting peptide responses were greater in diabetic patients than in control subjects as a consequence of the higher glycaemic stimulus. The contribution of incretin factors to total insulin responses was 72.8 +/- 6.9% (100% = response to oral load) in control subjects and 36.0 +/- 8.8% in diabetic patients (p less than or equal to 0.05). The contribution to connecting peptide responses was 58.4 +/- 7.6% in control subjects and 7.6 +/- 14.5% (p less than or equal to 0.05) in diabetic patients. Ratios of integrated insulin to connecting peptide responses suggest a reduced (hepatic) insulin extraction in control subjects after oral as compared to intravenous glucose. This was not the case in diabetic patients. Immunoreactive gastric inhibitory polypeptide responses were not different between control subjects and diabetic patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Measurement and partial characterization of the multiple forms of neurokinin A-like immunoreactivity in carcinoid tumours

An antiserum raised against neurokinin A has been used to demonstrate storage and release of neurokinin A-like immunoreactivity by carcinoid tumours. The antiserum showed reactivity towards members of the tachykinin family of polypeptides in the order: neurokinin A greater than eledoisin greater than neurokinin B greater than kassinin greater than substance P greater than physalaemin but the magnitude of the cross-reactivity with substance P and physalaemin was less than 1% of that of neurokinin A. A sensitive (IC50 238 fmol/ml; minimum detectable concentration, 9 fmol/ml) radioimmunoassay was set up using this antiserum. Extracts of metastatic tumour tissue from four patients with a primary carcinoid tumour in the midgut contained both neurokinin A-like immunoreactivity (NKA-LI) and substance P-like immunoreactivity (SP-LI). The concentrations (pmol/g wet weight) of NKA-LI and SP-LI in the tumours were: patient A 210, 201; patient B 2276, 6849; patient C 1198, 834 and patient D 424, 379. Analysis of the tumour extracts by reverse phase HPLC indicated that the NKA-LI was heterogeneous. Under two different conditions of chromatography, one component was eluted with the same retention time as neurokinin A. Two further components were more hydrophobic than neurokinin A but were not eluted with the retention time of neurokinin B. Analysis of these components by gel filtration indicated a molecular weight in the 3000-4000 range suggesting that they may be related to neuropeptide K, an N-terminally extended form of neurokinin A. NKA-LI and SP-LI were undetectable in the plasma of patients A and D but were elevated in patient B (NKA-LI 1005 +/- 114; SP-LI 345 +/- 85 fmol/ml) and patient C (NKA-LI 80 +/- 31; SP-LI 21 +/- 13 fmol/ml).

Effect of a specific serine protease inhibitor on the rat pancreas. II. Influence of camostate on the endocrine pancreas

Chronic oral administration of camostate, a specific serine protease inhibitor, is known to induce pancreas hypertrophy in rats. A possible influence of the protease inhibitor on the endocrine rat pancreas was studied using isolated perfused pancreas and islet incubations. The presence of camostate had no direct effect on the glucose-induced insulin release in vitro in concentrations from 1 microM to 1 mM, but enhanced the basal insulin release from islets cultured over 24 h in media containing the protease inhibitor (100 microM). Administration of camostate over 14 days to rats induced a remarkable hypertrophy of the pancreas without influencing plasma insulin or gastric inhibitory polypeptide levels and insulin concentration of the pancreas. Glucose-stimulated insulin release from the perfused pancreas was not increased despite significantly higher total insulin content. It is concluded that camostate exerts no direct effect on the glucose-stimulated insulin release and that chronic administration of the compound induces pancreas hypertrophy in vivo without influencing insulin release.

Hepatic artery embolization for treatment of endocrine gastrointestinal tumors with liver metastases

We report about six patients with endocrine gastrointestinal tumors and liver metastases (four insulinomas, one carcinoidtumor, one paraganglioma), who were treated with a transluminal embolization of the hepatic artery when cytostatic therapy was ineffective. In two patients a second embolization was necessary after recurrence of clinical symptoms. All patients tolerated the procedure without severe side-effects and improved clinically. Serum insulin levels and HIAA-secretion rapidly decreased. Survival lasted from 3 to 32 months (median 15 months). Five additional patients with metastatic endocrine gastrointestinal tumors, observed during the same time period, were regarded as not suitable for hepatic artery embolization. In selected patients, hepatic artery embolization may become an effective therapy for treatment of metastasing endocrine gastrointestinal tumors when conventional medication with cytostatic drugs has become ineffective.

[Effect of FOY-305 on the activity and secretion of pancreatic enzymes in vitro]

FOY-305, a synthetic inhibitor of serin-proteases, shows a highly specific inhibition of the activity of purified trypsin and tryptic activity from duodenal juice in a range of 1 to 10 microM. Phospholipase A2 is only partly inhibited (40%) by much higher concentrations of FOY-305 (100 microM to 1 mM), amylase activity is not affected by either concentrations. FOY-305 did not influence CCK-stimulated amylase- and trypsin-secretion from isolated pancreatic lobules in concentrations which inhibited completely tryptic activity.