Effect of CCK on food intake in man: physiological or pharmacological effect?

The present study was designed to determine in humans the dose of CCK which suppresses food intake. 18 male subjects received in randomized order either i.v. saline or Thr28 Nle31 CCK 25-33 (CCK-9) at 100 or 500 pmol/kgh, respectively. In addition, 7 subjects received CCK together with the opiate receptor antagonist naloxone to examine if activation of endogenous opioids might interfere with the potential satiating effect of CCK. Food intake during saline was 32 +/- 2 sandwiches (mean +/- SEM), during CCK-9 100 pmol/kgh 28 +/- 2 (n.s.) and only 12 +/- 3 during CCK-9 500 pmol/kgh (p less than 0.01). The respective water intake was 730 +/- 70 ml, 590 +/- 60 ml (n.s.) and 320 +/- 50 ml (p less than 0.01). Naloxone further reduced food and water intake during high but not low dose CCK or saline. During saline postprandial insulin levels rose by 49 +/- 6 microU/ml within 45 min which was attenuated during low dose (23 +/- 6 microU/ml; p less than 0.01) and high dose CCK-9 (1 +/- 1 microU/ml; p less than 0.001). Plasma glucagon did not change in control or CCK experiments. The postprandial rise of pancreatic polypeptide was attenuated during high dose CCK. Naloxone had no effect on the hormonal response except for a prolonged reduction of insulin and glucose levels following high dose CCK + naloxone. Plasma CCK levels rose by 5.4 pmol/l in controls but by 55 and 255 pmol/l during the low and high dose CCK infusion, respectively. These data demonstrate that suppression of food intake in man by i.v. CCK is a pharmacological rather than a physiological effect.(ABSTRACT TRUNCATED AT 250 WORDS)

Modulatory effect of insulin on rat small intestinal motility and peptide release in vitro

Intact segments of rat ileum were stimulated in vitro by either electrical field stimulation (EFS) or cholinergic stimulation with carbachol, in the presence of absence of varying insulin concentrations (50, 100 and 200 microU/ml), and the contraction in the longitudinal axis was recorded. Insulin had no significant influence on the carbachol contractile dose-response curve nor did it affect the cholinergically mediated 'on-contraction' at onset of the electrical stimulus. The 'off-contraction' occurring at cessation of the electrical stimulus was partly mediated by a cholinergic and partly by a noncholinergic and nonadrenergic mechanism, and decreased over time with repeated stimulation. This decay with time was significantly attenuated by insulin. In the presence of insulin, release of bombesin-like immunoreactivity induced by carbachol or EFS significantly increased. On the other hand, the release of somatostatin-like immunoreactivity was suppressed by 50-70% in the presence of insulin. These results demonstrate that in vitro insulin can modify both the motility responses of isolated segments of rat ileum and the neuropeptide release from such segments.

Percutaneous cholangioscopic or transpapillary insertion of self-expanding biliary metal stents

Fifty-two self-expanding metal stents were implanted in 39 patients with malignant (35 patients) or benign (4 patients) biliary stenoses. The stents were inserted and properly released by means of a 7 or 9 French gauge delivery catheter via the percutaneous (20 patients) or transpapillary (19 patients) route. In all cases the endoprostheses expanded to a diameter of 7 to 10 mm and achieved complete biliary tract drainage. Jaundice disappeared in 36 of the 39 patients. No early complication was observed. After a median follow-up of 121 days (range, 30 to 422 days), 19 of 36 patients are still alive and 17 died of non-procedure-related causes. Biliary re-obstruction occurred in five patients due to tumor overgrowth above or below the prosthesis (four patients) or bile encrustation (one patient). In patients with malignant stenoses, the probability of stent patency is 78% after 200 days. We conclude that large-bore metal stents are safe, effective, and provide better long-term patency than conventional endoprostheses.

Substitution of factor XIII: a therapeutic approach to ulcerative colitis

Three patients with ulcerative colitis in the active stage demonstrated reduced levels of F XIII activity and F XIII subunit A (61 and 80.3%, respectively). Because of the lack of clinical improvement during conservative therapy, the patients were treated additionally with F XIII concentrate (Fibrogammin HS, Behring, FRG) for 10 days. The substitution resulted in an increase in F XIII activity (144.3%) and F XIII subunit A (238%) as well as in a marked improvement in symptoms.

Effect of motilin on gastric emptying in patients with diabetic gastroparesis

OBJECTIVES

Because disturbances of gastric emptying are a serious complication in insulin-dependent diabetic subjects with regard to the maintenance of good metabolic control, we wanted to assess the effectiveness of motilin as a potential treatment for gastric emptying disturbances.

RESEARCH DESIGN AND METHODS

The intestinal hormone motilin has been shown to accelerate gastric emptying in healthy subjects. Therefore, we examined the effect of intravenous motilin on gastric emptying of a 99mTc colloid-labeled semisolid test meal in 9 insulin-dependent diabetic patients with diabetic gastroparesis. All patients had a significantly delayed gastric emptying rate compared with a group of 11 healthy control subjects.

RESULTS

During the infusion of motilin, gastric emptying was accelerated, and it was no longer significantly different from control values.

CONCLUSIONS

These data demonstrate that motilin and related compounds such as erythromycin derivatives could be useful for the treatment of disturbed gastric emptying in diabetic subjects.

Soluble interleukin-2 receptor and soluble CD8 in liver cirrhosis and obstructive jaundice

Activated lymphocytes secrete soluble interleukin-2 receptor (sIL-2R); CD8-positive lymphocytes secrete soluble CD8 (sCD8). Liver dysfunction in cirrhosis and obstructive jaundice is known to result in depressed cellular immunity. To evaluate whether this is due to real inactivation of the immune system, we measured sIL-2R and sCD8 in the serum of 46 patients with liver cirrhosis, 25 patients with obstructive jaundice, 32 patients with alcoholic liver disease without evidence of cirrhosis, 23 healthy persons and 43 patients with unrelated disease. sIL-2R in patients with cirrhosis (mean +/- s.e.m. 1499 +/- 140 U/ml) and obstructive jaundice (1517 +/- 204) was significantly increased compared with healthy subjects (363 +/- 29) and patients with unrelated diseases (685 +/- 92); sCD8 was significantly increased in patients with cirrhosis (737 +/- 63) but not in patients with obstructive jaundice (419 +/- 32) compared with healthy subjects (322 +/- 23) and patients with unrelated diseases (375 +/- 22). No difference was found between patients with cirrhosis due to alcohol abuse (n = 15) and chronic hepatitis B (n = 6). The Child-Pugh score had no significant influence on the sIL-2R or sCD8 value. In obstructive jaundice, sIL-2R correlated with alkaline phosphatase as marker of cholestasis (r = 0.43). These data show that in spite of the apparent depressed cellular immune defense both in liver cirrhosis and obstructive jaundice there is a general activation of the immune system but the CD8+ cell compartment is only activated in liver cirrhosis. The great changes of sIL-2R and sCD8 in liver dysfunction are important for the interpretation of studies using these serum proteins as markers for immune activation.

[Sonographic percutaneous drainage of liver abscesses]

13 patients with pyogenic liver abscess and five patients with amoebic abscess underwent percutaneous drainage of the abscesses using the Seldinger (n = 8) or trocar technique (n = 11). The results showed that the trocar method was easier and faster to perform and well tolerated by the patients. No complications were observed despite of one case of transient peritonitis caused by a dislocated catheter. One patient with pyogenic liver abscess died of septic shock. All other patients were successfully treated, using local drainage and systemic antibiotic therapy.

Vagally induced release of gastrin, somatostatin and bombesin-like immunoreactivity from perfused rat stomach. Effect of stimulation frequency and cholinergic mechanisms

The isolated stomach of rats was vascularly perfused to measure the secretion of gastrin, somatostatin (SLI) and bombesin-like immunoreactivity (BLI). The gastric lumen was perfused with saline pH 7 or pH 2, and electrical vagal stimulation was performed with 1 ms, 10 V and 2, 5 or 10 Hz, respectively. Atropine was added in concentrations of 10(-9) or 10(-7) M to evaluate the role of cholinergic mechanisms. In control experiments, vagal stimulation during luminal pH 2 elicited a significant increase of BLI secretion only at 10 Hz but not at 2 and 5 Hz. Somatostatin release was inhibited independent of the stimulation frequency employed. Gastrin secretion at 2 Hz was twice the secretion rates observed at 5 and 10 Hz, respectively. At luminal pH 7 BLI rose significantly at 5 and 10 Hz. SLI secretion was decreased by all frequencies. Gastrin secretion at 2 and 5 Hz was twice as high as during stimulation with 10 Hz. Atropine at doses of 10(-9), 10(-8), 10(-7) and 10(-6) M had no effect on basal secretion of BLI, SLI and gastrin. At luminal pH 2, atropine increased dose-dependently the BLI response at 2 and 5 but not at 10 Hz. The decrease of SLI during 2 and 5 Hz but not 10 Hz was abolished by atropine 10(-9) M. SLI was reversed to stimulation during atropine 10(-7) M at all frequencies. The rise of gastrin at 2 Hz was reduced by 50%. At luminal pH 7, atropine had comparable effects with a few differences: the BLI response at 10 Hz was augmented and the gastrin response to 2 and 5 Hz was reduced. In conclusion the present data demonstrate a frequency and pH-dependent stimulation of BLI and gastrin release. The stimulation of BLI is predominantly due to atropine-insensitive mechanisms while muscarinic cholinergic mechanisms exert an inhibitory effect on BLI release during lower stimulation frequencies (2 and 5 Hz) independent of the intragastric pH and also during higher frequencies at neutral pH. Both, atropine sensitive and insensitive mechanisms are activated frequency dependent. The atropine-sensitive cholinergic mechanisms but not the noncholinergic mechanisms involved in regulation of G-cell function are pH and frequency dependent. Somatostatin is regulated largely independent of stimulation frequency and pH by at least two pathways involving cholinergic mechanisms of different sensitivity to atropine. These data suggest a highly differentiated regulation of BLI, gastrin and SLI secretion and the interaction between these systems awaits further elucidation.

Effect of substance P and neurokinin A on rat parietal cell function

In enzymatically dispersed enriched (76%) rat parietal cells we studied the effect of substance P on acid sequestration as indirectly measured by [14C]aminopyrine accumulation. Substance P (10(-8)-10(-5) M) had no effect on basal [14C]aminopyrine accumulation. Yet, the peptide reduced the response to histamine and to the postreceptor agonists forskolin and dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP). Inhibition by substance P followed noncompetitive kinetics and reduced stimulated parietal cell function by up to 45% at 10(-5) M. The antagonist [D-Pro2, D-Trp7,9]-substance P at 10(-5) M partly reversed the inhibitory effect of substance P. Cholinergic stimulation of [14C]aminopyrine accumulation was not reduced by substance P. Neurokinin A, another tachykinin that is structurally related to substance P, was of comparable potency and efficacy in reducing [14C]aminopyrine accumulation in response to histamine, forskolin, and DBcAMP. Inhibition of forskolin- or DBcAMP-induced [14C]aminopyrine accumulation persisted in the presence of 10(-5) M ranitidine. Inhibition by substance P and neurokinin A of the response to histamine was not sensitive to pertussis toxin. Both tachykinins failed to reduce histamine- and forskolin-stimulated cAMP production. Our data suggest that substance P and neurokinin A exert a direct effect on rat parietal cells. They attenuate histamine-stimulated acid sequestration at an intracellular step that is distal to the adenylate cyclase and that does not involve pertussis toxin-sensitive GTP-binding proteins.

[Endosonographic diagnosis of pancreatic tumors]

140 patients (72 men, 68 women; mean age 57 [26-83] years) with suspected pancreatic tumours were investigated by endoscopic ultrasound (EUS) and also by conventional ultrasound, computed tomography (CT) and endoscopic retrograde cholangiopancreatography (ERCP). The EUS scans were performed with an echo-endoscope in the descending part of the duodenum (for the head of the pancreas) or in the stomach (for the body and tail). The definitive diagnosis or exclusion of a pancreatic tumour (malignant n = 85, benign n = 4, inflammatory n = 23, no tumour n = 28) was made at operation (n = 63), by needle biopsy (n = 35), at necropsy (n = 4) or by clinical follow up (n = 38, mean 10.5 months). The sensitivity and specificity of endoscopic ultrasound (99% and 100%) were superior to the results given by conventional ultrasound scans (71% and 39%), CT (82% and 46%) and ERCP (89% and 64%). This was also true of small tumours of 3 cm or less (EUS 100%, conventional ultrasound 57%, CT 68% and ERCP 89%). However, the differential diagnosis between malignant and inflammatory masses in the pancreas was not feasible by endoscopic ultrasound, either prospectively (detection rate 69%) or by comparative analyses of echo structure. Endoscopic ultrasound appears to be a valuable aid to the diagnosis or exclusion of pancreatic tumours. When conventional ultrasound and CT give negative or doubtful results it can be used in conjunction with or instead of ERCP to confirm the diagnosis.

Complications of diagnostic gastrointestinal endoscopy

Undesired side effects and complications of gastrointestinal endoscopy and premedication are rare events. However, this is true only of endoscopic units with experienced investigators, modern equipment and monitoring. The complication rate of upper gastrointestinal endoscopy is about 0.1% with cardiopulmonary events predominating. The typical complication of colonoscopy is perforation, seen in 0.2%. The relevant ERCP specific complication is acute pancreatitis in about 1%, followed by acute cholangitis. The most serious complications of laparoscopy are hemorrhage from the liver biopsy site, bleeding from abdominal wall varices, and perforation of the colon. The cardiopulmonary mortality is low for upper gastrointestinal endoscopy as well as for colonoscopy (1 death/20,000 procedures). Premedication, chronic obstructive pulmonary disease, coronary heart disease, valvular heart disease and, last but not least, advanced age, must be considered risk factors for the development of complications of gastrointestinal endoscopy. Balanced indication, particularly in the elderly patient, should be the consequence. If possible, endoscopy should be performed without sedatives. If premedication is necessary, it should be used sparingly. Not only patients at high risk for the development of cardiopulmonary complications, but all patients undergoing endoscopy must be carefully monitored after premedication, during and after endoscopy. The non-invasive procedure of pulse-oximetry is appropriate for continuous monitoring of arterial oxygen saturation in patients with cardiopulmonary diseases, irrespective of their premedication status. Antibiotic prophylaxis is recommended in patients with valvular heart disease or prosthetic valves. Standardized cleaning and disinfection of the instruments is of great importance to avoid hepatitis B or HIV transfer.(ABSTRACT TRUNCATED AT 250 WORDS)

Perspectives in "electronic endoscopy". Past, present and future of fibers and CCDs in medical endoscopes

Electronic endoscopy has undergone considerable evolution in recent years. Early instruments had poorer resolution than fiberscopes, and distorted colors significantly. The second generation of electronic endoscopes has been considerably improved, and electronic endoscopy is expected to play a major role in endoscopy in the next decade, with its enhanced teaching abilities, permanent image storage, reproduction and retrieval. An important new development has been the development of a high-resolution colonoscope & gastroscope. Electronic endoscopes are now able to produce better resolution than fiberscopes, and the future should bring further improvements in resolution with electronic instruments. A number of problems still remain to be solved with electronic endoscopy. Irregular reflection from secretions, food and blood at short focus (less than 1 cm) results in a loss of resolution, which makes electronic endoscopy particularly difficult when bleeding is brisk. Electronic endoscopes synthesize color from a strobed signal of red, blue and green in a processor. Color is dependent on brightness, and at close focus, excessive brightness in the center of the field results in erratic color reproduction. Images acquired at electronic endoscopy may be digitized for storage and processing in a computer--which, however, is not a straightforward task at the present time. Image processing in electronic endoscopy is still in its early stages, but we anticipate that new developments in early diagnosis, classification and measurement of lesions will take place. Digitized images can also be transmitted via telephone lines, and it will soon be possible to instantaneously send images across the world.

Frequency-dependent secretion of pancreatic amylase, lipase, trypsin, and chymotrypsin during vagal stimulation in rats

Pancreatic enzyme secretion in rats has been shown to be stimulated differentially by the intestinal hormones secretin and cholecystokinin. Since it is unknown if activation of neural mechanisms have similar effects, it was the aim of the present study to examine in anesthetized rats the output of the pancreatic enzymes amylase, lipase, trypsin, and chymotrypsin before (15 min), during, and after (30 min each) vagal stimulation (5 ms, 10 V) with different frequencies (0.5, 5, 10, and 50 Hz). At 5 Hz, a maximal stimulation of all four enzymes was observed, with a peak towards the end of the vagal stimulation period. At 0.5 Hz, amylase, trypsin, and chymotrypsin were released not only in smaller quantities but also in a different time pattern (trypsin and chymotrypsin), with a maximum early during vagal stimulation. Lipase secretion remained unchanged at 0.5 Hz. At 10 Hz, the output of amylase, lipase, and trypsin was quantitatively less compared to 5 Hz. In contrast to stimulation at 0.5 and 5 Hz, the maximal enzyme output was reached after cessation of vagal stimulation (amylase and lipase). Chymotrypsin release did not change in response to vagal stimulation at 10 Hz. A frequency of 50 Hz had no influence on the secretion of any of the four enzymes determined. These data demonstrate that activation of the vagus nerves can lead to a differential release of pancreatic enzymes. The exact regulatory mechanisms of action are as yet unknown and remain to be determined.

[Endoscopic and percutaneous implantation of self-expanding endoprostheses in biliary stenosis]

Self-expanding metal stents were implanted in 30 patients (14 men and 16 women, mean age 67 [40-86] years) with malignant (n = 27) or benign (n = 3) obstruction of the biliary tract (hepatic duct bifurcation: n = 14; choledochal duct: n = 16). The stents were introduced and left in place endoscopically in 13, percutaneously and transhepatically via a 7 or 9 F catheter in 17 patients. The stents, which expand to a diameter of 7-10 mm, in all cases achieved complete drainage, as confirmed by cholangiography. Jaundice completely disappeared in 28 of 30 patients. No complications were noted during a 30-day period of observation. After a median follow-up period of 90 days, 17 patients have been without jaundice for a median period of 141 (30-330) days. A recurrence of jaundice was noted in three patients (restenosis proximal to the stent in 2, incrustation with bile in one). Ten patients died, without any signs pointing to stent occlusion. These data indicate that the probability of stent patency in malignant stenoses of 200 days after implantation is 84%, so that stents in most cases provide a safe and effective means of drainage. Because they have a relatively large lumen with small surface area infection, occlusion and migration apparently occur less often than with conventional synthetic prostheses.

Electromagnetic shock-wave lithotripsy of gallbladder calculi. Multicentered preliminary report on experience with 276 patients

The Lithostar Working Group reports on the first 276 patients who underwent lithotripsy of biliary calculi by means of an electromagnetic Lithotriptor (Lithostar Plus from Siemens). Some 66% (183/276) and 27% (75/276) of the patients had solitary and two or three stones, respectively while 7% (18/276) had more than three gallbladder calculi. Calcified calculi were found in 11% of the patients. On an average the patients were treated in 1.6 (range 1.4-2.15) sessions; with the exception of one user the maximal energy (setting 9) was applied. The upper limit of shock waves per session was 1500-6000 (x = 2189 +/- 1058). 17% and 48% of the patients were free from calculi after 3 and 6 months, respectively. During the follow-up period 14% of the patients complained of severe biliary pain and 1.5% suffered from pancreatitis, which was controlled by conservative treatment. In three out of five patients with a transitory cholestatic jaundice endoscopic papillotomy was necessary. Four patients underwent an elective cholecystectomy. Considering the selection of the patients, the results obtained are comparable with those found in other studies.

[Extracorporeal shockwave lithotripsy of pancreatic calculi]

Extracorporeal shock-wave fragmentation of pancreatic stones is a complementary non-surgical treatment in selected patients with chronic pancreatitis. The procedure has proven to be safe and technically effective. Preliminary clinical results indicate therapeutic success rates in terms of pain disappearance or reduction in more than 90% of the patients. The indication should be taken into consideration before surgical intervention.

Effect of N-butylscopolamine on sphincter of Oddi motility in patients during routine ERCP--a manometric study

N-butylscopolamine is a generally accepted drug for the suppression of gut motility. Although it is used during routine ERCP, only few systematic studies have been carried out in patients to investigate its action on sphincter of Oddi motility. In the present study the effect of N-butylscopolamine on the motility of the sphincter of Oddi region has been evaluated in 17 patients undergoing routine diagnostic ERCP. The pressure parameters of these patients were compared with "normal values" obtained in 23 volunteers. A dose of 40 mg of N-butylscopolamine bromide (Buscopan) i.v. significantly reduced the contraction frequency of the sphincter of Oddi from 5.4 +/- 1.2/min to 1.0 +/- 1.4/min (p less than 0.001), the contraction amplitude from 106.3 +/- 27.8 mmHg to 55.2 +/- 23.5 (p less than 0.01) mmHg, and the basal sphincter of Oddi pressure from 13.9 +/- 3.0 mmHg to 11.0 +/- 3.5 mmHg (p less than 0.05), but had no effect on the pressure gradient between the common bile duct and the duodenum. These results clearly demonstrate that N-butylscopolamine inhibits contractions of the sphincter of Oddi, and may thus facilitate the intubation of the papilla.

Comparison of GLP-1 (7-36amide) and GIP on release of somatostatin-like immunoreactivity and insulin from the isolated rat pancreas

The effect of equimolar doses of GIP and GLP-1 (7-36amide) on insulin and somatostatin secretion in the isolated perfused rat pancreas was compared. At a perfusate glucose concentration of 70 mg/dl GLP-1 (7-36amide) 10(-9) and 10(-8) M and GIP 10(-9) M elicited a significant stimulation of insulin while GIP 10(-8) M and lower doses of both peptides (10(-11) and 10(-10) M) were ineffective. At elevated perfusate glucose levels of 150 mg/dl both peptides stimulated insulin release at 10(-11), 10(-10), 10(-9) and 10(-8) M but not at 10(-12) M. The insulin response at the higher glucose level was significantly greater compared to the effect of the same doses at normoglycemic conditions. Somatostatin release was stimulated significantly by GLP-1 (7-36amide) at 10(-10) and 10(-9) M at perfusate glucose level 70 mg/dl. At a glucose concentration of 150 mg/dl this effect was abolished. GIP did not alter somatostatin release at a perfusate glucose concentration of 70 mg/dl while at 150 mg/dl only the highest dose of GIP (10(-8) M) stimulated somatostatin release significantly. In conclusion, the present data demonstrate that in vitro in the rat pancreas both peptides are equally effective secretagogues of insulin release at normal and moderately elevated perfusate glucose levels. In contrast, somatostatin secretion is stimulated by GLP-1 (7-36amide) at normoglycemic conditions while only a rather high and presumably pharmacological dose of GIP is a stimulus of somatostatin secretion at moderate hyperglycemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Bombesin-like peptides stimulate gastrin release from isolated rat G-cells

Bombesin-like peptides as well as receptor-independent activators were tested for their effect on gastrin release from acutely dispersed rat gastric G-cells. The amphibian peptide bombesin as well as its mammalian analogues neuromedin B and neuromedin C stimulated gastrin release. Maximal responses were achieved with 10(-9) M bombesin (191.0 +/- 16.8% of basal release), 10(-8) M neuromedin C(205.9 +/- 17.6%) and 10(-7) M neuromedin B (162.2 +/- 10.4%), respectively. The phorbol ester 12-O-tetradecanoyl-phorbol 13-acetate (TPA) and the synthetic diacylglycerol analogue 1-oleoyl-2-acetyl-sn-glycerol (OAG) are receptor-independent activators of the protein kinase C. Both TPA (10(-6) M) and OAG (10(-5) M) stimulated gastrin release to 214.0 +/- 29.3% and 198.2 +/- 20.8% of basal, respectively. Calcium ionophore A23187 (10(-5) M) was the most effective stimulant tested (364.7 +/- 39.6%). Its effect was reversed by the calmodulin antagonist W 7 (10(-6)-10(-5) M). Finally, forskolin (10(-5) M), a direct activator of cAMP-formation, as well as the cAMP-analogue dbcAMP (10(-3) M) induced gastrin release. IN conclusion, neuromedin B is less potent and less effective than neuromedin C and bombesin in stimulating rat gastric G-cells. In addition, gastrin release is activated by calcium- and phospholipid-dependent as well as by cAMP-induced cellular signal transduction mechanisms.