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Biomedical subjects

R L Riepl

Publications and source records attributed to R L Riepl.

At least 37 records · Page 2Linked to original sources
PubMed1996

Suppression of vagus-mediated pancreatic polypeptide release by the mu-opiate receptor agonist loperamide in man.

1. Morphine suppresses the release of pancreatic polypeptide, a hormone under vagal cholinergic control. The intention of the study was to detect whether the mu-opiate receptor agonist loperamide is also able to inhibit pancreatic polypeptide release, and to define its site of action. 2. In groups of healthy subjects (n = 6 each) stimulation of pancreatic polypeptide was assessed in five different tests: (i) insulin-hypoglycaemia; (ii) modified sham feeding; (iii) intravenous infusion of the cholecystokinin analogue ceruletide; (iv) injection of corticotropin releasing hormone; (v) infusion of the muscarinic acetylcholine agonist bethanechol. All tests were performed after oral application of either a placebo or loperamide (16 mg), tests (ii) and (iii) were repeated with loperamide in smaller doses (2 and 6 mg), with loperamide plus naloxone, with naloxone alone, and with infusion of atropine. Plasma concentrations of pancreatic polypeptide were measured radioimmunologically. 3. Release of pancreatic polypeptide in test (i) to (iv) was completely blocked by 16 mg loperamide, whereas bethanechol-stimulated release (test 5) was not influenced. Tests (ii) and (iii) showed that the inhibition was dose-dependent and could be attenuated by naloxone. The inhibitory effect of loperamide was comparable with that of atropine. 4. We conclude that loperamide causes a dose-dependent inhibition of pancreatic polypeptide release mediated by vagal-cholinergic pathways, but does not have an atropine-like peripheral action.

Adult↗
PubMed1996

Comparison of the effects of the M1-receptor antagonist telenzepine and the CCK-receptor antagonist loxiglumide on the pancreatic secretory response to intraduodenal tryptophan in dogs.

In six conscious dogs with chronic gastric and pancreatic fistulas we compared the action of different doses (20.25 to 81.0 nmol/kg/h) of the muscarinic M1-receptor antagonist telenzepine, the cholecystokinin (CCK) antagonist loxiglumide (2.5 to 10.0 mg/kg/h) and several combinations of both drugs on the pancreatic secretory response to intraduodenal perfusion of graded loads of tryptophan (0.37-10.0 mmol/h) given against a background of secretin (20.5 pmol/kg/h i.v.). Except for 20.25 nmol/kg/h telenzepine, all tested doses of telenzepine and/or loxiglumide decreased the 180-min integrated bicarbonate response to tryptophan by 55 to 119%. Except of 20.25 nmol/kg/h telenzepine and/or 2.5 mg/kg/h loxiglumide, all tested doses of telezepine and/or loxiglumide inhibited the tryptophan stimulated integrated pancreatic protein responses by 54 to 88%. While telenzepine mainly inhibited the bicarbonate and protein response to the lower loads of tryptophan (0.37-1.1 mmol/h), loxiglumide decreased the response to all loads of tryptophan. The inhibition evoked by the combinations of telenzepine and loxiglumide was not significantly greater than that by single infusion of either drug. The CCK plasma levels basally and in response to tryptophan were not significantly altered by telenzepine and/or loxiglumide. These findings indicate that (1) both enteropancreatic cholinergic reflexes and the hormone CCK are mediators of the protein response to intraduodenal trytophan (2) enteropancreatic cholinergic reflexes are probably the dominant mediators of the response to low amounts of tryptophan, whereas CCK is the major mediator of the response to high loads of tryptophan, (3) the two mediators seem to act independently of each other, and (4) the release of CCK by intestinal trytophan is not influenced by telenzepine or loxiglumide.

Animals↗
PubMed1996

Decreased substance P levels in rectal biopsies from patients with slow transit constipation.

OBJECTIVE: Previous studies in patients with chronic constipation found abnormalities in the nervous tissue of the large intestine, predominantly in the muscularis externa. Since there is evidence that the nervous system of mucosa and submucosa is also involved in the control of colonic motility we investigated the contents of vasoactive intestinal polypeptide (VIP), somatostatin and substance P in rectal biopsies of patients with slow colonic transit constipation. DESIGN AND METHODS: Twenty-two patients (17 females, 5 males) with chronic slow transit constipation (oro-anal transit with radio-opaque markers on high fibre diet > 70 h) and long-term use of laxatives, and 20 controls (12 females, 8 males) with no history of constipation, were included in this study. Large rectal biopsy specimens including the submucosa were obtained from 5 cm above the dentate line and frozen in liquid nitrogen. After microdissection of the biopsies into mucosa and submucosa the neuropeptides were extracted by boiling and homogenizing the tissue in acetic acid and determined using validated radioimmunoassays. RESULTS: Patients with slow transit constipation showed, compared to healthy controls, significantly lower levels of the excitatory neurotransmitter substance P in the mucosa and submucosa of rectal biopsies. There was no difference between the two groups concerning the levels of the inhibitory neurotransmitters, VIP and somatostatin. CONCLUSION: Slow transit constipation is associated with abnormalities of the substance P content of the enteric nervous system of mucosa and submucosa. This seems not to be related to chronic laxative use, since anthranoids cause a reduction in the levels of inhibitory neurotransmitters (VIP, somatostatin), but not of substance P, in the rat colon.

Biopsy↗
PubMed1996

M1 muscarinic mechanisms regulate intestinal-phase gallbladder physiology in humans.

The contribution of muscarinic receptor subtypes to biliary control mechanisms is unclear. We investigated stimulated gallbladder function and release of associated hormones during M1-receptor blockade. Following a double-blind, randomized, crossover protocol, healthy volunteers each received placebo and telenzepine, a selective M1-receptor antagonist, as 2-h background infusion. Gallbladder contraction (by ultrasonography), bilirubin output, and release of cholecystokinin (CCK) and pancreatic polypeptide (PP) were assessed during increasing doses of endogenous (intraduodenal nutrient) and exogenous (hormonal) stimulation. All parameters were stimulated in a dose-dependent manner on placebo days. Contractile and secretory responses to low-dose caerulein (CCK analogue) were inhibited by 60-80% under telezepine, whereas high-dose (supraphysiological) stimulation overrode this effect. Similar inhibition was achieved during nutrient stimulation. CCK plasma levels rose during endogenous and exogenous stimulation but were unaffected by M1 blockade, whereas stimulated PP release was completely inhibited (> 100% decrease), reflecting suppressed vagal tone. Selective M1-receptor blockade inhibits the physiological response of the gallbladder in humans; this effect cannot be attributed to suppressed CCK release. Our findings support the hypothesis that CCK acts at the gallbladder via cholinergic nerves under physiological conditions. Viewed with our previous observations, nonselective antagonism of biliary function by atropine is primarily mediated through M1 muscarinic pathways.

Adult↗
PubMed1996

Comparison of the effects of two cholecystokinin-receptor antagonists, loxiglumide and L-364,718, on the pancreatic secretory response to intraduodenal tryptophan in dogs.

BACKGROUND: The aim of the study was to compare the effects of the cholecystokinin (CCK)-receptor antagonists loxiglumide and L-364, 718 on the endogenously stimulated pancreatic exocrine secretion. METHODS: In six conscious dogs with chronic gastric and pancreatic fistulas we compared the action of different doses of loxiglumide (2.5 to 10.0 mg/kg/h) and L-364, 718 (0.025 to 0.1 mg/kg/h) on the pancreatic secretory response to intraduodenal perfusion of graded loads of tryptophan (0.37-10.0 mmol/ h), given against a background of secretin (20.5 pmol/kg/h intravenously). RESULTS: Both loxiglumide and L-364, 718 inhibited the secretin-stimulated pancreatic bicarbonate output by up to 47% and 48%, respectively. The pancreatic protein output during secretin was significantly inhibited by all doses of L-364,718 (by 65% to 82%) but not by loxiglumide. All doses of loxiglumide and L-364, 718 abolished the 180-min integrated bicarbonate response to tryptophan. The two higher doses of loxiglumide (5.0-10.0 mg/kg/h) and L-364,718 (0.05-0.1 mg/kg/h) significantly decreased the 180-min integrated response to tryptophan by 59% and 79% (loxiglumide) and by 72% and 97% (L-364, 718). The plasma CCK-like immunoreactivity basally and in response to tryptophan was not significantly altered by loxiglumide or L-364, 718. CONCLUSIONS: These findings indicate that in dogs 1) the pancreatic bicarbonate response to secretin is augmented by the hormone CCK; 2) L-364, 718 but not loxiglumide decreases pancreatic protein output during secretin; 3) endogenous released CCK is involved in the pancreatic bicarbonate response and is a major mediator of pancreatic protein response to intraduodenal tryptophan; and 4) the release of CCK by intraduodenal tryptophan is not influenced by loxiglumide and L-364, 718.

Animals↗
PubMed1996

Maldigestion after total gastrectomy is associated with pancreatic insufficiency.

OBJECTIVES: Subsequent to total gastrectomy, many patients develop maldigestion and weight loss. The mechanisms that underlie these changes are not known. Therefore, in a prospective study, we have analyzed endocrine and exocrine pancreatic function in patients before and 3 months after total gastrectomy. METHODS: In 15 patients (12 male, three female, median age 62.4 yr) undergoing total gastrectomy due to gastric cancer, a direct exocrine pancreatic function test (secretin-cerulein test) was performed. In addition, a standard test meal was given to all patients to study endocrine pancreatic function and the pattern of hormones that influence exocrine pancreatic secretion. In nine patients, both function tests were repeated 3 months after total gastrectomy. Before and at 11 points after the application of the test meal, blood samples were taken for the measurement of glucose, insulin, glucagon, gastrin, pancreatic polypeptide, and cholecystokinin. In addition, a secretin-cerulein test was performed to analyze trypsin, chymotrypsin, amylase, bicarbonate, and the juice volume in the duodenal aspirates. RESULTS: Three months after total gastrectomy, all patients exhibited severe primary exocrine pancreatic insufficiency. Secretin-cerulein tests revealed that pancreatic juice secretion, trypsin, chymotrypsin, and amylase were significantly reduced by 76%, 89%, 91%, and 72%, respectively, 3 months after total gastrectomy and secretin and cerulein stimulation. Post-operatively, the patients had a pathological glucose tolerance with increased postprandial insulin and glucagon secretion. The baseline and postprandial gastrin and pancreatic polypeptide secretion were significantly decreased after total gastrectomy. In contrast, early postprandial cholecystokinin secretion was significantly increased postoperatively. CONCLUSIONS: After total gastrectomy, patients develop severe primary exocrine pancreatic insufficiency with decreased gastrin, decreased late postprandial pancreatic polypeptide, and increased cholecystokinin levels. These findings may explain why many patients with total gastrectomy have maldigestion and weight loss postoperatively. Therefore, gastrectomized patients should be given pancreatic enzymes to avoid these symptoms.

Ceruletide↗
PubMed1996

[Clinical aspects, pathophysiology, diagnosis and therapy of gastrointestinal manifestations of progressive systemic scleroderma].

About 50% of patients with progressive systemic sclerosis develop significant clinical involvement of the alimentary tract. In decreasing order of frequency esophagus (75%), anorectum (50-70%), small bowel (50%), colon (40%) and stomach (40%) can exhibit characteristic morphological or functional features. Typical symptoms of reluxesophagitis and severe constipation are often reported. Beside this, diarrhea, steatorrhea and malnutrition are common complaints. Manometric and electrophysiological studies brought evidence of a neuropathy of the enteric nervous system in the early stages of the disease, resulting in disturbances of the digestive and interdigestive peristalsis and therefore e.g. leading to gastroparesis, bacterial overgrowth of the small intestine or constipation. In late PSS collagen deposition and atrophy of the smooth muscle layer of the bowel wall cause loss of function of sphincters as the lower esophageal sphincter or the anal sphincter and marked atony of parts of the intestine. The diagnostic procedures consist of esophageal manometry, 24-h pH-metry, esophageal and gastric radionuclide transit studies, H2-breath tests, barium enemas, anorectal manometry and endoscopy. Therapeutic options include H2-antagonists, proton-pump inhibitors, prokinetic drugs, octreotides and antibiotics. Nutritional supplementation and surgical interventions are often of limited therapeutic value. Finally in some cases long-term total parenteral nutrition is warranted.

Digestive System↗
PubMed1995

Cholecystokinin and pancreatic polypeptide release in diabetic patients with and without autonomic neuropathy.

The present study was undertaken to investigate postprandial responses of cholecystokinin (CCK) and pancreatic polypeptide (PP) and their interrelationship in patients with diabetes mellitus (DM) with and without autonomic neuropathy (AN). Twenty-two patients with DM (seven with AN and 15 without AN) and 14 age-matched healthy controls were studied. AN was diagnosed according to several tests of cardiovascular autonomic function. CCK and PP plasma levels were measured by specific radioimmunoassays before and at several time points after the oral administration of a test meal. Basal CCK plasma levels in DM patients were normal, whereas basal PP plasma levels were increased (139 +/- 18 vs 72 +/- 7 pg/ml; P < 0.01). Integrated postprandial CCK response was increased in DM patients (208 +/- 27 vs 110 +/- 14 pmol/liter/2 hr; P < 0.05), mainly due to the patients with AN. Postprandial PP response was increased in DM patients without AN (37,273 +/- 5241 vs 13,418 +/- 3299 pg/ml/2 hr; P < 0.001) but not in those with AN (8887 +/- 3461 pg/ml/2 hr). Moreover, PP response was closely (P < 0.002) correlated with the degree of AN. A direct and linear correlation between postprandial CCK and PP responses was found in healthy controls (r = 0.78; P < 0.005) but not in DM patients. We conclude that the CCK response to a meal is increased in diabetic patients with AN, whereas the PP response is increased only with an intact autonomic nervous system.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Effects of long-term treatment with anthranoids and sodium picosulphate on the contents of vasoactive intestinal polypeptide, somatostatin and substance P in the rat colon.

OBJECTIVE: To examine the effects of chronic treatment and a single high-dose application of anthranoids and sodium picosulphate on the neuropeptide content of the rat colon. DESIGN AND METHODS: Over a 6-month period, eight groups of rats were each given one of the following: sennosides or sodium picosulphate in low daily doses (10 and 2.5 mg/kg/day, respectively), in high daily doses (40 and 10 mg/kg/day, respectively), and in high twice-weekly doses (30 and 7.5 mg/kg/day, respectively); high daily doses of danthron (500 mg/kg/day); and vehicle (tragacanth 0.5%) only. Four further groups of rats each received a single dose of vehicle or a high dose of one of the three laxatives. All rats were killed 48 h after the last dose. The ascending and descending colon were removed and separated into mucosa, submucosa, and muscularis externa. Vasoactive intestinal polypeptide (VIP), somatostatin, and substance P were extracted by boiling and homogenizing the tissue in acetic acid, and their levels were determined using validated radioimmunoassays. RESULTS: After long-term treatment with high doses of sennosides and danthron, but not after a single high-dose administration, there was a significant reduction in mucosal levels of VIP and somatostatin and in submucosal levels of somatostatin of both colonic segments, as well as in the level of VIP in the muscularis externa of the descending colon. Substance P levels remained unaffected. Sodium picosulphate had no effect. CONCLUSIONS: Chronic treatment with anthranoids in high doses, but not with sodium picosulphate, reduces VIP and somatostatin levels in the rat colon. This may represent damage to the enteric nervous tissue or a pharmacological effect of the anthranoids, causing decreased synthesis or increased breakdown of these peptides.

Animals↗
PubMed1995

[Gastrointestinal involvement in progressive systemic scleroderma].

The complained gastrointestinal symptoms in PSS are probably caused by several complex disturbances like intestinal transit disturbances (ITD), bacterial overgrowth of the small intestine caused malabsorption of bile acids and altered kinetics of intestinal hormones. 25 patients with PSS and eleven healthy controls were tested for the existence of ITD by use of the metal-detector test (MDT). Twelve patients were also tested for a malabsorption of primary bile acids by radioimmunological measurement of clolylglycine serum levels before and after a meal. In addition serum concentrations of gastrin (nine patients) and plasma concentrations of cholecystokinin (CCK) (eight patients) and motilin (eleven patients) were measured by radioimmunoassay pre- and postprandial. Interdigestive gastric emptying was accelerated in patients with PSS (53 +/- 3 min. vs. 73 +/- 7 min.; p<0.01). Small intestinal transit times were similar in both groups (115 +/- 17 min. vs. 121 +/- 13 min.). Colonic transit in patients with PSS was significant prolonged (63 +/- 6 h vs. 39 +/- 5 h; p<0.05). There were no significant differences between the two groups concerning the pre- and postprandial levels of cholylglycin. Basic and postprandial levels of gastrin, CCK and motilin were higher in the PSS group. In contrast to scintigraphic studies using semisolid meals gastric emptying of the copper pellet in PSS was accelerated. A general malabsorption of primary bile acids was not found. Prolonged colonic transit times correlate well with frequently complained obstipation. Gastric hypacidity could be the reason of elevated gastrin levels. The high motilin-levels in PSS could be due to a lack of the feed-back inhibition as a result of diminished phase-III activity of the interdigestive migrating motor complex. The elevation of CCK-levels could reflect compensation of neurogenic or myogenic disturbances of gallbladder contraction.

Adult↗
PubMed1994

Relationship between postprandial release of CCK and PP in health and in chronic pancreatitis.

The aim of this study was to investigate the relationship between postprandial release of cholecystokinin (CCK) and pancreatic polypeptide (PP) in healthy subjects and patients with chronic pancreatitis (CP). 14 patients with CP and 14 age-matched healthy subjects were studied. Diagnosis of CP was confirmed by standardized imaging modalities (ERCP and CT). Exocrine pancreatic function was assessed in all 28 subjects using the pancreolauryl serum test (PLT). An oral test meal was administered to stimulate endogenous hormone release. Plasma samples were taken before and at several time points after the test meal. CCK and PP plasma levels were measured by specific radioimmunoassays. Basal CCK and PP plasma levels were not different between patients with CP and controls, and were not correlated in either group. However, a direct linear correlation between integrated postprandial release of CCK and PP was found in healthy subjects (r = 0.74, P < 0.005). This postprandial coupling was not evident in patients with CP (r = 0.16; n.s.). Peak fluorescein serum concentration in patients with CP and steatorrhea (SCP) (n = 6) was < 2.5 micrograms/ml, and CCK and PP responses to the meal were significantly impaired (CCK response = 61 +/- 14 pmol/l/120 min in SCP vs. 110 +/- 14 in controls, P < 0.05; PP response = 3920 +/- 1773 pg/ml/120 min in SCP vs. 13418 +/- 3299 in controls, P < 0.05). In patients with mild/moderate exocrine insufficiency, CCK and PP responses varied greatly and were not different from controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Effect of intraduodenal bile and taurodeoxycholate on exocrine pancreatic secretion and on plasma levels of vasoactive intestinal polypeptide and somatostatin in man.

Intraduodenal (i.d.) application of bile or Na-taurodeoxycholate (TDC) dose dependently enhances basal exocrine pancreatic secretion. The hydrokinetic effect is mediated at least in part by secretin. This study should show, whether vasoactive intestinal polypeptide (VIP), a partial agonist of secretin, may also be involved in the mediation of the hydrokinetic effect. Furthermore, plasma concentrations of somatostatin-like immunoreactivity (SLI) were measured in order to check whether this counterregulating hormone is also released by bile and TDC. Twenty investigations were carried out on 10 fasting healthy volunteers provided with a double-lumen Dreiling tube. Bile and TDC were intraduodenally applied in doses of 2-6 g and 200-600 mg, respectively, at 65-min intervals. Plasma samples were withdrawn at defined intervals for radioimmunological determination of VIP and SLI. Duodenal juice was collected in 10-min fractions and analyzed for volume, pH, bicarbonate, lipase, trypsin, and amylase. I.d. application of bile or TDC dose dependently stimulated hydrokinetic and ecbolic pancreatic secretion. Bile exerted a slightly stronger effect than TDC. Pancreatic response was simultaneously accompanied by a significant increase of plasma VIP and SLI concentrations. The effect of bile on integrated plasma VIP and SLI concentrations seems to be dose dependent; the effect of TDC on integrated SLI, too. For the increase of integrated plasma VIP concentrations after TDC no dose-response relation could be established. We conclude that VIP may be a further mediator of bile-induced volume and bicarbonate secretion.(ABSTRACT TRUNCATED AT 250 WORDS)

Amylases↗
PubMed1994

In man the mu-opiate agonist loperamide specifically inhibits ACTH secretion induced by the cholecystokinin-like peptide ceruletide.

Ceruletide, a cholecystokinin-8-like peptide, was recently reported to stimulate ACTH secretion in man. The aim of this study was to investigate the effect of the mu-opiate agonist, loperamide, and the opiate antagonist, naloxone, on ceruletide-induced ACTH secretion in man. In 6 normal subjects, basal ACTH and cortisol plasma levels were significantly suppressed 3 h after loperamide administration (16 mg, orally) from 5 +/- 0 to 2 +/- 0 pmol/l and from 356 +/- 44 to 154 +/- 16 nmol/l. After stimulation with 8 ng ceruletide/kg body weight/min over a period of 5 min, the maximum ACTH levels (at 7.5 min) were significantly reduced by loperamide from 26 +/- 7 to 6 +/- 1 pmol/l and the maximum cortisol levels (at 30 min) were significantly reduced from 676 +/- 47 to 392 +/- 58 nmol/l. Furthermore, the ACTH peak (delta = 7.5 min) was significantly blunted by loperamide from 21 +/- 7 to 5 +/- 1 pmol/l and the integrated area under the curve from 0 to 120 min (delta AUC) of ACTH was significantly reduced from 40 +/- 11 to 14 +/- 4 pmol x 120 min/l. The cortisol peak (delta = 30 min) and the AUC of cortisol were not significantly diminished. The suppressive effect of loperamide on basal and ceruletide-induced ACTH and cortisol secretion was completely reversed by the administration of 0.8 mg naloxone, 20 min before and during infusion of ceruletide. The administration of naloxone itself had no significant effect on ACTH or cortisol levels. In conclusion, ACTH is released by peripherally administered ceruletide within a short period.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocorticotropic Hormone↗
PubMed1994

Postprandial release of cholecystokinin and pancreatic polypeptide in health and in gallstone disease: relationships with gallbladder contraction.

OBJECTIVES: The present study investigated endogenous postprandial release of cholecystokinin (CCK) and pancreatic polypeptide (PP) in relation to gallbladder dynamics in healthy subjects and patients with gallstones. METHODS: Gallbladder volume (by ultrasonography) and plasma concentrations of CCK and PP (by radioimmunoassay) were evaluated in 18 patients with gallstones and 14 healthy controls before and after administration of a semi-liquid test meal (250 ml, 1450 kJ). Gallbladder contractility was previously assessed on a separate day by intravenous infusion of ceruletide (2.5 ng/kg/min). RESULTS: Basal gallbladder volume was not different in patients (32 +/- 5.9 cm3) and controls (26 +/- 2.7 cm3). Postprandial gallbladder contractility was impaired in gallstone patients, who showed a reduced integrated response (-3718 +/- 349 vs. -5251 +/- 376 cm3/2 h, p < 0.01) and a delayed time to maximal gallbladder contraction (67 +/- 7.4 min vs. 37 +/- 2.4 min, p < 0.002). Maximal gallbladder contraction after ceruletide infusion was also reduced (44.1 +/- 5.0% vs. 72.5 +/- 3.2%, p < 0.001), but not delayed (15.8 +/- 2.4 vs. 15.7 +/- 1.4 min) in gallstone patients. Basal CCK and PP plasma levels were similar in both groups. Postprandial CCK release was impaired in gallstone patients, predominantly due to a decreased response over the first 30 min (3.8 +/- 1.8 vs. 20.0 +/- 4.9 pmol/L/30 min, p < 0.005). Postprandial PP release was not different between groups. A direct linear correlation between postprandial release of CCK and PP was found in healthy controls but not in patients with gallstones. Postprandial gallbladder volume at any moment was inversely correlated with CCK plasma levels in healthy subjects, but not in gallstone patients. No correlation between postprandial PP response and gallbladder dynamics was observed. CONCLUSIONS: Based on a multivariate logistic approach, a reduced and delayed postprandial gallbladder contractility and an impaired CCK release in the early postprandial phase are significantly associated with gallstone disease. Our data provide further evidence for the predominant role of endogenous postprandial CCK release in gallbladder contraction. A role for PP in modulating postprandial gallbladder dynamics is not supported.

Cholecystokinin↗
PubMed1993

[Broad beans as a cause of acute hemolytic anemia].

A previously healthy 17-year-old Greek boy suddenly developed jaundice of sclerae and skin. In addition, physical examination revealed a pale appearance. He also reported feeling tired and weak. The haemoglobin level was 9.6 g/dl, lactate dehydrogenase activity 335 U/l, bilirubin concentration 3.2 mg/dl (direct bilirubin 0.7 mg/dl, indirect bilirubin 2.5 mg/dl), haptoglobin concentration 48.8 mg/dl. As haemolytic anaemia was assumed, direct questioning elicited the fact that the patient had, for the first time in his life, eaten 300 g of broad beans (Vicia faba) on each of two days, namely 3 and 2 days before the appearance of jaundice. Absence of glucose-6-phosphate dehydrogenase activity in the red blood corpuscles confirmed the diagnosis of favism. On symptomatic treatment both the enzyme activities and the bilirubin level fell to normal within one week, and the haemoglobin level was 15.7 g/dl after 4 weeks.

Acute Disease↗
PubMed1993

The mediators of bile action on the exocrine pancreas.

Under basal conditions, bile and bile salts applied intraduodenally influence plasma levels of several gastroenteropancreatic peptides. Besides those with stimulatory effects on exocrine pancreatic secretion, others with inhibitory or no effects are released as well. Furthermore, cholinergic and peptidergic neural mechanisms may also be activated. Secretin seems to be the most important mediator of bile- or bile salt-induced water and bicarbonate secretion. In addition, VIP released from peptidergic nerve endings in the pancreas may also be involved in the mediation of the hydrokinetic effect. With regard to water and bicarbonate secretion, cholinergic mechanisms probably are of minor importance. Cholinergic mechanisms, however, seem to be the most important mediator of bile- or bile salt-induced pancreatic enzyme secretion. CCK may act as an additional mediator of the ecbolic effect. This statement, however, is based on few results only and has to be confirmed by further studies. Gastroenteropancreatic peptides with an inhibitory action on the exocrine pancreas were also released by intraduodenal bile or bile salts. Somatostatin is released in physiologically relevant amounts to bring about a counter-regulation. Plasma PP levels are also enhanced by bile and bile salts. The amounts of PP released, however, are below those observed postprandially. In contrast to their stimulatory action on basal pancreatic secretion, bile and bile salts have no or even an inhibitory effect on pancreatic secretion stimulated by intraluminal nutrients. Accordingly, the release of gastroenteropancreatic peptides is not influenced (for example, secretin) or even reduced (for example, CCK) when bile or bile salts are added to intraluminal nutrients.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗