Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1432-0428
    Keywords: Isolated islets ; insulin release ; glucagon ; glucose ; cyclic adenosine monophosphate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Glucose stimulation increased the cAMP content of collagenase-isolated rat pancreatic islets fourfold above baseline values. The elevation was transient, lasting about 5 min, and was dose-dependent. Insulin release continued at a constant rate throughout the incubation. — Glucagon, in the absence of glucose, increased cAMP for about 1 min, but only slightly, and had no effect on insulin release. In the presence of glucose, however, glucagon enhanced islet cAMP content 15-fold and increased the release of insulin. Glucagon was most effective at high glucose concentrations (16.6 and 25 mM). — This indicates that glucagon is critically dependent on the presence of glucose in order to increase the islet cAMP content and to stimulate insulin release. The inability of glucagon to generate sufficient cAMP in the absence of glucose might be one of the reasons why the hormone is a potentiator rather than an initiator of insulin release.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-0428
    Keywords: GIP ; gastrin ; insulin ; incretin ; chronic pancreatitis ; test meal ; malassimilation of fat
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Twenty-nine patients with chronic pancreatitis had a significantly greater IR-GIP response to a test meal than 15 controls. This increased response was not related to the degree of steatorrhoea or glucose intolerance. It was most marked in a group of patients with moderately impaired IRI release and medium steatorrhoea. From this is concluded that the IR-GIP response to a test meal is determined by at least two factors: 1. feedback control via insulin secretion, 2. assimilation of fat. In chronic pancreatitis endocrine insufficiency may induce an exaggerated GIP response and severe exocrine insufficiency may prevent fat induced GIP release. Gastrin is not involved in the different GIP response in patients with chronic pancreatitis.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1432-0428
    Keywords: GIP release ; chronic pancreatitis ; steatorrhea ; maldigestion ; pancreatin ; incretin effect
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The influence of impaired digestion on nutrient induced release of gastric inhibitory polypeptide (GIP) and insulin have been investigated in patients with chronic pancreatitis. All patients had massive steatorrhea (〉25 g/24 h), and glucose intolerance. A standard liquid test meal comprising fat and glucose were ingested with or without pancreatic enzyme substitution (9.0 g pancreatin). In the presence of pancreatin the response of serum levels of GIP to the test meal was significantly enhanced (81.2 vs 194.5 μg/l×180 min). Concurrently, the insulin response was augmented (3.4 vs 6.4 U/l×180 min), resulting in improved glucose tolerance. Addition of pancreatin also significantly augmented the GIP response to oral fat (100g), but not to oral glucose (100g). In patients with pancreatogenic steatorrhea the insulin response to an IV glucose infusion (0.7g/ kg/h for 90 min) was augmented by oral fat only after addition of 9.0 g pancreatin to the fat load (3.5 vs 7.3 U/l×180 min). After restoration of the GIP response to fat by pancreatin, the inhibitory effect of IV glucose on fat-induced GIP increase was restored. These data indicate that the GIP response to a mixed meal or triglycerides is dependent on the absorption of nutrients. In patients with chronic pancreatitis improvement of pancreatogenic insufficiency reverses the impaired GIP response, restores the incretin effect of fat, and improves glucose tolerance.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-0428
    Keywords: GIP release ; insulin release ; obesity ; glucose intolerance ; starvation ; food restriction ; weight reduction ; oral glucose load ; test meal ; triglyceride ingestion
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The response of serum immunoreactive gastric inhibitory polypeptide (IR-GIP) and immunoreactive insulin (IRI) to a liquid mixed test meal, glucose or fat has been examined in obese subjects before and after starvation or reduced caloric intake (800 calories). Basal serum levels of IR-GIP increased significantly during starvation of obese persons and remained elevated over the whole starvation period while basal serum IRI levels decreased. The exaggerated IR-GIP response of obese subjects with normal or pathological glucose tolerance to a test meal and of obese subjects with glucose intolerance to 100 g glucose ingestion decreased significantly after starvation or food restriction. Simultaneously, the serum IRI response decreased. The exaggerated IR-GIP response of obese subjects to oral triglycerides which did not affect serum IRI or glucose levels was also significantly decreased after food restriction. The IR-GIP response of obese subjects to a test meal was already reduced after 5 days of food restriction together with an improved glucose tolerance. At this stage the IRI response was unchanged. After weight reduction in obese subjects there was a significant decrease of the IRI response to oral but not to intravenous glucose, while the glucose response decreased irrespectively of the mode of glucose administration. The IR-GIP response decreased only after oral glucose. The data are compatible with the hypothesis that the exaggerated IR-GIP response of obese subjects to oral glucose or fat load is secondary to the increased food intake and that changes in IRI response to oral glucose are related to changes in IR-GIP response.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1432-0428
    Keywords: GIP ; gastrin ; insulin ; incretin ; coeliac disease ; duodeno-pancreatectomy ; chronic pancreatitis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The response of serum immunoreactive gastric inhibitory polypeptide (IR-GIP), gastrin (IRG) and insulin (IRI) to a mixed standard meal was measured in 15 controls, 6 patients with coeliac disease, 26 patients with chronic pancreatitis and 6 patients with chronic pancreatitis and partial duodenopancreatectomy (Whipple's procedure). Serum levels of IR-GIP, IRG and IRI were significantly reduced in patients with coeliac disease. The serum glucose increase was significantly smaller only during the first hour after the meal. Since small intestinal GIP- and G-cells are situated mainly in the glands of duodenal and jejunal mucosa their absolute number is not significantly reduced in coeliac disease. It is suggested that the release of IR-GIP and duodenal IRG is influenced by the rate of absorption of nutrients. In patients with chronic pancreatitis the IR-GIP release is significantly greater than in controls, the IRG release normal and the IRI response delayed. After Whipple's procedure the IR-GIP response is increased significantly while the IRG secretion is abolished. This demonstrates that the duodenum is not necessary for GIP release and that pancreatic and jejunal gastrin are without clinical significance.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Diabetologia 28 (1985), S. 565-573 
    ISSN: 1432-0428
    Keywords: Incretin ; entero-insular axis ; insulinotropic factors ; GIP ; hepatic insulin extraction ; pancreatic denervation ; Type 2 diabetes ; experimental diabetes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experimental and clinical work over the last 6 years has confirmed and broadened, but also challenged, the incretin concept. The nervous component of the entero-insular axis is still poorly defined, especially the peptidergic nerves, of which several contain insulinotropic regulatory peptides. The incretin effect is preserved after complete denervation of the porcine pancreas. Type 2 (non insulin-dependent) diabetic patients have a significantly decreased incretin effect. GIP (gastric inhibitory polypeptide; glucose dependent insulin releasing peptide) remains the strongest incretin factor. Its secretion depends on the absorption of nutrients. However, the correlation between the GIP response and disturbances of the entero-insular axis in some gastrointestinal diseases and, in particular, Type 2 diabetes, is poor. Furthermore, physiological concentrations of exogenous GIP do not produce fully the incretin effect and injection of GIP antibodies does not abolish the incretin effect. This suggests the existence of additional humoral incretin factors. On the other hand, GIP seems to have direct metabolic effects independent of its insulinotropic activity. The incretin effect of oral glucose is smaller if plasma levels of C-peptide rather than insulin are measured. However, decreased hepatic extraction of insulin after glucose ingestion only accounts partially for the incretin effect. GIP is unlikely to be the gut factor which regulates hepatic insulin extraction.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1432-0428
    Keywords: GIP release ; insulin release ; obesity ; pathological glucose tolerance ; feedback control of GIP secretion ; test meal ; triglyceride ingestion ; oral glucose load
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary To investigate the possibility that an abnormality of the entero-insular axis is responsible for the hyperinsulinaemia of obesity, serum immunoreactive gastric inhibitory polypeptide (IR-GIP) and insulin (IRI) were measured after the ingestion of a liquid mixed test meal, glucose or fat, in normal weight and obese subjects. The latter were divided into a group with normal oral glucose tolerance (nOGT) and a group with pathological glucose tolerance (pOGT). Fasting levels of IR-GIP were significantly elevated in the obese group with pOGT. After the mixed meal the overweight subjects showed a significantly greater response of IR-GIP than the controls, with highest levels in the pOGT group. Simultaneously, the IRI response was significantly greater in the obese subjects than in the controls. The increases of IR-GIP and IRI after an oral load of 100 g glucose were normal in the obese subjects, but showed a significantly greater integrated response in the obese patients with pOGT. The ingestion of 100 g fat induced no IRI release but a significantly greater release of IR-GIP in the obese subjects, irrespective of their glucose tolerance. It is concluded that fat is a stronger releaser of IR-GIP than glucose. The effect of a combined load of glucose (30 g) and fat (100 g) was also compared in obese and normal weight subjects with the effect of either alone. Fat but not glucose released significantly more IR-GIP in obese subjects. In normal weight controls, but not in obese subjects, the IR-GIP release after fat plus glucose became significantly smaller than after fat alone. Since only the combined ingestion of glucose and fat and not fat alone releases insulin it is suggested that endogenous insulin inhibits GIP release and that this feedback control between insulin and GIP is defective in patients with obesity.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Applied physics 14 (1977), S. 155-159 
    ISSN: 1432-0630
    Keywords: 42.65 ; 71.20
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract We report for the first time stimulated magneto-Raman scattering inp-type InSb. Two different Raman scattering processes were observed. The first one has a Raman shift of about 2cm−1/kG and is observed at magnetic fields up to 30kG. The other one is observable only at high magnetic fields above 30kG and shows Raman shifts between 1.2cm−1 and 3.0cm−1 with a tuning rate of about 0.2cm−1/kG. The first process can be interpreted either as spin-flip Raman scattering by photo-excited electrons in the conduction band or as Raman scattering by holes in the valence band involving transitions from heavy to light hole states. The other Raman shift observed seems to occur on account of transitions between the heavy hole ladders.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Springer
    European journal of pediatrics 150 (1991), S. 339-342 
    ISSN: 1432-1076
    Keywords: Glucose tolerance ; Turner syndrome ; Insulin ; GIP
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract There is a well documented increase in the incidence of abnormal glucose tolerance in patients with Turner syndrome. To elucidate the pathophysiology of this phenomenon, we studied the serum concentrations of gastric inhibitory polypeptide (GIP) — as probably the most important hormonal factor of the entero-insular axis — in relation to impaired glucose tolerance in this syndrome. Oral glucose tolerance tests were performed in 12 Turner patients with simultaneous determination of plasma glucose, insulin and GIP. An impaired glucose tolerance (iGT) was found in four patients with a chronological age between 12.3 and 14.9 years. These patients were compared with found Turner patients of similar age and weight and a normal glucose tolerance (nGT). The highest insulin level occurred 90 min after stimulation in the patients with iGT compared to 30 min in the nGT group. Interestingly, the total areas under the insulin curves were not different. Stimulated plasma GIP concentrations and the areas under the GIP curves wer significantly lower in iGT compared to nGT patients. A disturbed entero-insular axis might contribute to the delayed — rather than diminished — release of insulin in patients with Turner syndrome and impaired glucose tolerance.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 1432-1041
    Keywords: Emiglitate (BAY o 1248) ; sucrose ; starch ; postprandial hyperglycaemia ; glucosidase inhibitor ; blood glucose ; serum insulin ; serum GIP ; breath hydrogen ; adverse effects
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The absorbable deoxynojirimycin derivative emiglitate (BAY o 1248) is a potent competitive inhibitor of small intestinal α-glucosidases in man. In two similar randomized, placebo-controlled, double blind investigations, the efficacy, duration of action and tolerability of single doses of 10, 20 and 40 mg emiglitate have been assessed in healthy male volunteers after repeated sucrose or maize-starch loads at 08.00, 12.00 and 17.00 h. Even at the lowest dose used, emiglitate almost abolished the glycaemic (−88%) and hormonal responses after the first sucrose meal, simultaneously evoking significant hydrogen evolution (mean peak H2-concentration 〉100 ppm), which was not related to the dose, and which induced unacceptable symptoms of carbohydrate malabsorption, i.e. at the dosages tested, the inhibition of glycaemic and hormonal responses was at the expense of intolerable gastrointestinal adverse effects. Flattening of postprandial responses of blood glucose, serum insulin and gastric inhibitory polypeptide was still apparent after a second sucrose load 4 h later, demonstrating long-lasting inhibition of α-glucosidase activity. After starch, the dose dependency of inhibition emerged more clearly than after sucrose, i.e. the reduction was less pronounced. However, emiglitate led to significant reduction of the glycaemic and hormonal rises after both the first and second starch meals. Symptoms of carbohydrate malabsorption were absent after 10 mg and were negligible with 20 mg or 40 mg emiglitate. Breath hydrogen concentration increased gradually, indicating slight but significant carbohydrate malabsorption after the highest dose of the α-glucosidase inhibitor. The results show that a single morning dose of 20–40 mg emiglitate might be useful in the control of postprandial hyperglycaemia after breakfast and lunch. This dose of the inhibitor was effective after either both 50 g starch or 50 g sucrose as the substrate, but was only tolerable after the starch meal.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...