Effects of cardioselective and non-cardioselective beta-blockade on adrenaline-induced metabolic and cardiovascular responses in man

In 12 normal volunteers the interaction between the metabolic and cardiovascular effects of adrenaline and either a cardioselective (atenolol 150 mg p. o. for 1 week) or a non-selective beta-blocker with intrinsic sympathomimetic activity (pindolol 15 mg p. o. for 1 week) were studied. Equiactive doses of the beta-blockers were investigated with respect to their metabolic effects. There were profound differences in the metabolic profile of the two substances: the non-cardioselective beta-blocker caused significant inhibition of the lipolytic, glycogenolytic and the growth hormone-releasing effects of adrenaline when compared to the cardioselective agent. The results indicate that, during non-cardioselective beta-blockade, metabolic effects occur which should favourably influence myocardial oxygen consumption by making myocardial performance more economical.

Biologic activities of biosynthetic human insulin in healthy volunteers and insulin-dependent diabetic patients monitored by the artificial endocrine pancreas

This study investigates and compares biosynthetic human insulin (BHI) and purified pork insulin, in healthy volunteers and in insulin-dependent diabetic patients, in terms of biologic action, capacity for controlling diabetic patients, and the requirements of the patients on each insulin. The possible importance of this new insulin in the improved long-term control of diabetic patients led to the experimental design of this protocol.

Behavior of secretion in the hypoxia-immobilisation stress on the rat

Secretin was determined radioimmunologically in portal vein blood and in duodenal mucosa biopsies in stressed male Wistar rats as compared to control animals. The stressed animals showd a significantly higher scretin content of the duodenalmucosa and no different levels of the portal vein blood. A stress ulcer-reducing cimetidine application does not demonstrate any influence of secretin content on duodenal mucosa. The obvious elevation of duodenal secrtin is not the result of an increased gastric acid production, but may be a consequence of a stress-reduced susceptibility of the pancreas to endogenous secretin.

The validity of C-peptide measurement in the diagnosis of factitious hypoglycemia

The case is presented of a 32-year-old obese diabetic nurse, with a history of recent hypoglycemic episodes. Estimation of immunologically measurable insulin during hypoglycemia after an overnight fast revealed high values, while simultaneous determination of serum C-peptide failed to show an increase. This combination is considered pathognomonic for factitious hyperinsulinism. After the hidden vial was discovered and presented to her, the patient finally admitted that she had been surreptitiously injecting insulin.

Effect of somatostatin on bile-induced acute hemorrhagic pancreatitis in the dog

In 21 female Beagle dogs an experimental pancreatitis was induced by injection of bile into the pancreatic duct system. Beside controls, dogs received 62.5 micrograms/h cyclic somatostatin (SRIF) a continuous i.v. infusion starting with a bolus of 250 micrograms 15 minutes before or 2 hours after bile injection. Following blood parameters were determined: lipase, amylase, blood count, minerals, glucose, insulin, gastrin, secretin and CCK. Two controls died within 24 hours, the others were sacrificed after 48 hours. All pancreata were examined morephologically. The controls developed all clinical signs of acute hemorrhagic pancreatitis, whereas all SRIF-treated dogs were in much better general condition. Lipase and amylase increased in all groups. In the controls insulin, gastrin and secretin remained unchanged and CCK rose slightly. SRIF-treatment diminished insulin, CCK and the test meal-induced increase of secretin. At autopsy the pancreata of the controls were nearly entirely apoplectic. The SRIF-treated dogs showed less damage of the pancreas and no severe hemorrhagic necrosis was noted. The beneficial effect of SRIF cannot only be due to an interaction with intestinal hormones. An additional direct protective effect on the exocrine parenchyma is proposed to exist.

[A field study with the combination of Pindolol and Clopamid in antihpertensive therapy (author's transl)]

In a field study comprising 678 patients with arterial hypertension efficacy and tolerance of the stable combination VKB 105 consisting of 10 mg Pindolol (Visken) and 5 mg Clopamid (Brinaldix) were investigated. Treatment with 1--2 tablets of VKB per day resulted in a successful therapy in 94% of all patients corresponding on the average to a reduction in blood pressure to 145/85 mm Hg within 14 days. In mean arterial pressures ranging between 120 and 170 mm Hg a positive linear relationship between the individual initial value and the hypotensive effect of the combination could be observed. A controlled omission trial disclosed qualitatively the respective contribution to the effect of the two components Pindolol and Clopamid. With a systematic case control of the serum potassium under the combined therapy with VKB 105 and during a monotherapy with Clopamid and antihypokalaemic effect of Pindolol could be demonstrated diminishing the tendency for potassium loss. The result revealed a far-reaching potassium neutrality of diuresis-depending stimulation of renin by the beta-receptor blocker. In 61 patients altogether subjective side-effects could be recorded, such as vertigo (5%), palpitations (2.8%), fatigue (2%), insomina (1.9%), nausea (1.7%) and vomiting (0.8%). Laboratory controls gave no indication for clinically relevant changes.

[A new method for determination of cadmium in plasma (author's transl)]

Cadmium can be isolated from plasma by formation of negative charged iodide complexes bound to an anion exchange resin. Elution from the resin gives a cadmium solution with only a few interfering substances in an uniform matrix. Thus an undisturbed determination by flameless atomic absorption spectrometry is achieved. The mean of the natural cadmium level found in plasma was 1.9 +/- 0.8 ng/ml, within the normal range between 1.1 and 3.3 ng/ml.

Insulin therapy in relation to circulating C-peptide levels

Part 1. Beta-cell secretion was stimulated maximally by an intravenous glibenclamide-glucose load in four groups of 10 adultonset diabetics divided according to their therapy, which was determined by clinical criteria. Under the standardized conditions of this test, the 20 patients requiring insulin had a mean fasting blood glucose (BG) of 255 mg./100 ml. and showed no stimulation of immunoassayable C-peptide (IMCP) by glibenclamide-glucose. In contrast, the mean fasting BG was 160 mg./100 ml., but the IMCP rose in patients who were able to be managed with sulfonylurea tablets. These differences in IMCP proved to be of value for the clinician in predicting the efficacy of diabetes therapy with either insulin or sulfonylurea tablets.

Part 2. Twenty-four-hour profiles of BG and IMCP were per performed in 28 insulin-requiring diabetics (age range: 14 to 74 years) who were 66 to 111 per cent of normal weight and had had diabetes for 0.2 to 31 years. These patients were divided into diabetics with IMCP (n = 14) and without IMCP (n = 14); the mean age and weight were similar in the two groups. The mean IMCP value and its standard deviation correlated inversely with the mean blood glucose (MBG) in all diabetics and healthy subjects. According to clinical criteria, diabetes control was better in the patients with IMCP. Analysis of variance showed that the mean BG concentrations for diabetics with and without IMCP were statistically different (p<0.02). Patients with IMCP were found to inject less insulin daily, and six of them were adequately treated with only one daily injection.

The effect of somatostatin on platelets: in vivo and in vitro studies

The influence of somatostatin on platelets was studied in healthy volunteers. After a bolus injection of 250 microgram somatostatin followed by a three hour infusion at a rate of 250 microgram somatostatin/hr a statistically significant fall of platelet count and impairment of platelet aggregation was observed. The aggregation inhibiting effect of somatostatin at the end of the three hour infusion is clinically unimportant as compared to the effect of aspirin. In vitro concentrations up to 10.0 microgram somatostatin per ml do not show any effect on platelet aggregation and platelet stickiness. Endocrinologically active doses of somatostatin in short term infusions are very unlikely to cause bleeding disorders.

[Insulin treatment of decompensated diabetes mellitus with a new artificial endocrine pancreas (author's transl)]

During the past decades insulin has been given in relatively high doses when treating diabetic coma. Recently low-dose insulin treatment has been proposed by several groups. In the reported investigation insulin was initially given in moderate to high doses (12-200 U/h) with a steady reduction in dose during the course of treatment. Insulin infusion was regulated either manually with an adjustable infusion pump (7 patients) or automatically with an artificial endocrine pancreas (glucose-controlled insulin infusion system; 11 patients). Thus 18 patients with decompensated diabetes mellitus (coma or precoma) were treated. In 14 patients with ketoacidotic decompensation laboratory data on hospital admission were: blood glucose 7.35 +/- 0.61 g/l, serum potassium 4.7 +/- 0.4 mmol/l, pH 7.1 +/- 0.04, base excess - 19,7 +/- 2.2 mmol/l (x +/- SEM). The other patients had hyperglycaemic or hyperosmolar non-ketotic decompensation. In all patients controlled reduction of blood glucose levels was achieved within 2.3 to 18 hours. The amounts of insulin infused during this ranged from 17 to 320 units, but in one instance was 1950 units. There were no complications.

Estimation of cholecystokinin-pancreozymin (CCK) in human plasma and tissue by a specific radioimmunoassay and the immunohistochemical identification of pancreozymin-producing cells in the duodenum of humans

A reliable, sensitive, reproducible and specific radioimmunoassay for cholecystokinin-pancreozymin (CCK) has been developed, using rabbit antisera to highly purified porcine hormone. The natural occurring variant of CCK (39-CCK), in which the ordinary CCK is lengthened from its N-terminus by a hexapeptide, labelled with 125J, and repurified by column chromatography on Sephadex G-10 and on SP-Sephadex C-25, was used as tracer. Separation from antibody-bound labelled 39-CCK was carried out using a double antibody procedure. Non-specific interference with the assay system was abolished by ethanol extractions. Highly purified porcine CCK was used as standard. No significant crossreaction was found with gastrin, motilin, vasoactive polypeptide (VIP), gastric inhibitory polypeptide (GIP), natural and synthetic secretin, pancreatic glucagon or insulin. The sensitivity of the assay is approximately 40 pg/ml of test solution. The mean immunoreactive CCK concentration in 45 fasting normal subjects was 222 pg/ml increasing after food ingestion to 480 pg/ml. Somatostatin was able to abolish the stimulated CCK release. Elevated CCK concentrations were found in chronic pancreatitis. Immunohistochemical identification of pancreozymin cells was carried out either in surgical samples or in biopsy material. Approximately 1650 CCK cells per cross-section in the duodenum of humans have been found. The CCK cells usually appeared elongated, oval or pyramidal in shape and were observed to reach the lumen with their apical cell pole.

Inhibition of cholecystokinin-pancreozymin release by somatostatin

To determine the effect of somatostatin on cholecystokinin-pancreozymin (C.C.K.) release, serum-C.C.K. concentrations were measured in normal volunteers after intraduodenal olive oil, with and without a simultaneous intravenous infusion of somatostatin. After instillation of the olive oil there was a rapid rise in serum-C.C.K. (integrated response 19 682+/-5632 pg min ml-1). This rise was completely abolished by somatostatin (integrated response -373+/-330 pg min ml-1, P less than 0-005) and rebound hyper-secretion was seen after the infusion had been stopped. These findings indicate that somatostatin may be involved in regulating C.C.K. release after meals, and suggest a possible explanation for the profound steatorrhoea seen in a patient with a somatostatin-producing tumour.

Somatostatin modulation of pancreatic glucagon, insulin, glucose and free fatty acids following beta-adrenergic stimulation

This study was undertaken to determine the effect of somatostatin on acute, orciprenaline mediated, beta-adrenergic stimulation of free fatty acids, blood glucose, insulin, and glucagon in healthy subjects. After orciprenaline and somatostatin insulin and glucagon decreased, whereas blood glucose and free fatty acids increased, probably in part as a result of the lesser inhibition of glucagon (50%) than of insulin (83%). From these observations it is tentatively concluded that the inhibitory effects of somatostatin on insulin and glucagon release in man are a consequence of beta-adrenergic receptor involvement. These effects are possibly mediated through increased destruction of cAMP, blocking of camp dependent secretion or impairment of calcium uptake.

Prevention by somatostatin of rise in blood pressure and plasma renin mediated by beta-receptor stimulation

The interrelationships of increased plasma renin and elevated blood pressure following acute beta-stimulation by orcipernaline and its prevention by somatostatin was studied in normal man. During somatostatin infusion basal values of renin and blood pressure were unchanged. Following orciprenaline both variables increased significantly. Combination of somatostatin and orciprenaline reduced the rise in plasma renin activity by 49%, mean arterial blood pressure by 21% and heart rate by 19%, compared with beta-stimulation alone. The results indicate that the inhibitory action of somatostatin on plasma renin activity may be mediated via beta-receptors. The lesser increase of blood pressure under somatostatin plus orciprenaline also indicates a possible inhibitory effect of somatostatin on beta-adrenergic receptors.

Concentrations of prostaglandin A-, E- and F-like substances in gastric mucosa of normal subjects and of patients with various gastric diseases

1. Prostaglandin A-, prostaglandin E- and prostaglandin F-like substances were determined radioimmunologically in antral biopsy material obtained by endoscopy. 2. In patients with gastritis, the concentrations of prostaglandin (E+A)-like substances were six times as high and of prostaglandin F-like substances twice as high as in normal subjects. In chronic atrophic gastritis, the concentrations of prostaglandin (E+A)-like material was four times as high as in normal subjects whereas prostaglandin-F like material remained unchanged. In acute gastric ulcer, prostaglandin (E+A)-like material reached concentrations four times times higher than in normal subjects, accompanied by a fivefold increase of prostglandin F-like substances. After healing of the gastric ulcer, prostaglandins returned to normal values. 3. There was no correlation between gastrin and prostaglandins in all biopsy specimens.

Effects of somatostatin and human gastrin I on the lower esophageal sphincter in man

The influence of gastrin and somatostatin on the lower esophageal sphincter was investigated in a total of ten metabolically healthy volunteers and one patient with Zollinger-Ellison syndrome. It could be shown that only unphysiologically high concentrations of gastrin produce a rise in pressure in the lower esophageal sphincter, while somatostatin has neither an effect on the lower esophageal sphincter pressure, nor is it able to inhibit the pharmacological effect of exogenic gastrin administration. The results of this study demonstrate that normal levels of serum gastrin do not seem to have much effect of resting LES pressure, nor does somatostatin. (Gastrin, in fact, in pharmacologic dosage does have an effecton the tonicity of the lower esophageal sphincter.)

A reliable method for generating antibodies against pancreozymin, secretin and gastrin

High specific antibodies against the gastrointestinal hormones pancreozymin, secretin, and gastrin were generated by coupling these peptides with N,N'-carbonyldiimidazole to bovine serum albumin. None of the antisera showed any cross reaction with gut and pancreatic hormones tested for cross reactivity. The dilution of antisera which were useful for the detection of 5-250 pg of hormone in human serum were 1:150 000 for secretin, 1:2000 for gastrin, and 1:2000 for pancreozymin. The N,N'-carbonyldiimidazole reagent is therefore highly effective for binding labile peptides to protein carriers without destroying the immunogenic features.

Prevention of stress ulcer by somatostatin in rats

In animal experiments it was examined, to what extent prophylactic application of Somatostatin is able to prevent the stress-induced ulcer of the rat. 32 male Wistar rats were exposed to a combined immobilisation-hypoxia-stress. Somatostatin was given intraperitoneally as bolus and intravenously as a continuous infusion. The results indicated that Somatostatin lowers significantly the incidence rate of stress-induced gastric ulcers in the rat.

Coagulation studies and platelet function after somatostatin infusion

The effect of short- and long-term somatostatin (GIF) administration on haemostatic function in man was investigated. The dosage programme applied in this study was 250 mug GIF as a bolus injection and 250 mug GIF/h by way of infusion. In five healthy volunteers a short-term (3h) treatment resulted in a statistically significant drop of platelet count and impairment of platelet aggregation at the end of infusion. However, these changes were within the physiologically normal range and disappeared after two hours on all subjects. Other parameters such as bleeding time, thromboplastin and partial thromboplastin time, fibrinogen, fibrin/fibrinogen split products, plasma factor XIII, ethanol gelation test were not affected. In two patients with gastric haemorrhage and persistent amylasaemia a 67 or 120-h treatment induced no remarkable haemostatic defect. By contrast, peptic ulcer bleeding in one patient stopped 60 min after starting the GIF infusion. These studies indicated that somatostatin administration in man at the dosage programme used neither results in clinical evidence indicating bleeding tendency nor does it influence laboratory parameters in an apparent way.

Gastrin concentration in plasma of the neonate at birth and after the first feeding

Plasma gastrin was determined simultaneously in 19 newborn infants and their respective mothers shortly after birth and in ten neonates before and after the first feeding. The gastrin concentrations in the umbilical vein plasma of the newborn infants were significantly higher than in the peripheral vein plasma of their mothers. The values were statistically not different from those obtained in the neonates before the first feeding. There was an increase in gastrin concentrations after the first feeding. From these results it is suggested that gastrin is produced in the neonate independently from the mother. It is already secreted after the first feeding. Experiments in rats showed that 125I-gastrin is not transported through the placenta. From these findings we assume that most likely the gastrin measured in plasma of newborn infants is of neonatal origin.

Human C-peptide. Part II: Clinical studies

Human C-peptide is determined by radioimmunoassay. On gel filtration of serum from a healthy subject and from a patient with islet cell carcinoma, C-peptide (MW 3025) appears ahead of insulin (MW 5808) and shows much higher molar concentrations than the hormone. Human proinsulin cross-reacts with our antiserum to synthetic human C-peptide. On direct determination of immunomeasurable C-peptide (IMCP) in fasting serum of 25 healthy subjects we find an average of 1.8 (+/- 0.4) ng/ml, corresponding to 60.4 X 10(-11) Mol/l. The molar concentration is about five-fold as compared to IMI (immuno-measurable insulin). IMCP and IMI patterns are not identical on stimulation of beta-cell secretion in healthy subjects by i.v. glucose or glucose-glibenclamide. This is probably due to differences in peripheral metabolism of both compounds. We conclude from our results that C-peptide determined in peripheral venous serum is a better indicator of beta-cell secretion than is insulin. Among 26 insulin-treated juvenile diabetics 15 show not measurable and 11 subnormal IMCP levels in fasting serum. No rise in IMCP is found 1-2 h following breakfast. Four juvenile patients receiving no insulin in a phase of total diabetes remission have normal or raised fasting IMCP concentrations. Only 2 out of 24 adult diabetics (16 treated with insulin and 8 with tablets) show non-measurable fasting IMCP concentrations, in another 4 patients values are below and in the remaining 18 cases above 1 ng/ml serum. Stimulation of beta-cell secretion through glucose-glibenclamide is more or less impaired in all adult diabetics compared to the healthy subjects.

Hypergastrinemia induced by glucocorticoid and corticotropin treatment in man

To elucidate further the pathogenesis of steroid-induced ulceration, plasma gastrin levels, both basal and after a test meal, were studied in normal volunteers and patients treated with glucocorticoids or corticotropin. In normal subjects the acute intravenous administration of 100 mg prednisolone had no effect on plasma gastrin levels. After oral administration of prednisolone (40 mg daily, for four days) a significant increase of the basal, the reactive, and the over 90-min integrated gastrin release was observed. In this group, the glucocorticoid treatment had a slight, but significant influence on gastric acid and pepsin secretion, while acidity and pepsin output stimulated by pentagastrin was not affected. In patients treated with prednisolone for more than 24 weeks, the oral administration of this hormone failed to alter basal gastrin values but affected significantly secretion after the test meal. In patients with multiple sclerosis, after intramuscular administration of corticotropin (60 IU daily, for 12 days), an increase of the basal, the reactive, and the integrated gastrin release also was found. Glucocorticoid-induced hypergastrinemia provides information on the pathogenesis of steroid-induced ulceration.

Inhibition of frusemide-induced hyperreninaemia by growth-hormone release-inhibiting hormone in man

In a study of the effect of somatostatin (growth-hormone release-inhibiting hormone) on plasma-renin in healthy volunteers, plasma-renin activity was measured by radioimmunoassay after the intravenous administration of somatostatin and also during frusemide-induced hyperreninaemia. While somatostatin was being given, basal values of renin were unchanged. Injection of frusemide alone produced hyperreninaemia; but, under somatostatin, renin release was inhibited by 45%. The results indicate that somatostatin is a potent inhibitor of renin and exerts its effect independent of sodium excretion, which was unchanged under somatostatin. Conceivably, somatostatin plays an important role in the regulation of endogenous renin release.

[Interaction between gastrointestinal hormones and endocrine regulation]

The vicinity of several hormone-producing glands as part of the anatomy of the intestinal tract and the resulting interaction has been confirmed by the discovery of hormonal factors of a specifically gastro-intestinal origin. Today we are mainly interested in the interaction between intermediary metabolism and incretory intestinal function; this is characterized by the joint action of conventional glandular hormones such as insulin and pancreatic glucagon as well as by the incretion of diffuse intestinal organs, hormones such as secretin, pancreozymin, motilin, VIP and GIP. The latter are at present subject of active research with the object of discovering their physiological significance be it as tissue hormones or as humoral agents with a "long distance" impact; their role within pathophysiology is also of interest. GIP ("gastric inhibitory peptide"), apart form acting upon the intestinal tract, also causes a marked rise in insulin production; this GIP possibly is the factor responsible for the difference in glucose tolerance following i. v. or oral administration of glucose, something that scientists have been trying to discover for a long time. We have also endeavored to investigate somatostatin. This substance was originally discovered as a hypothalamic factor with inhibitory action on growth hormone secretion; in the meantime, however, cells containing and possibly also producing somatostatin have also been detected in the intestine and particularly in the islets of Langerhans (D-cells). Since somatostatin inhibits insulin secretion and especially glucagon release as well as the exretory functions of the stomach and of the pancreas, the significance of this hormone possibly is that of a tissue hormone with inhibitory action on adjacent cells. As factor inhibiting both endocrine and exocrine secretory processes it would combine these two complexes. The possible therapeutic significance of somatostatin administration to diabetics would lie in the saving of insulin. A third sector of present-day research deals with the interaction between the calcium metabolism and the hormones involved as well as the intestine. We know that patients suffering from primary hyperparathyroidism are prone to contract stomach ulcers and pancreatitis; patients with a gastrinoma and a hyperfunction of the epithelial bodies suffer from a Zollinger-Ellison-sindrome and this again suggests association with endocrine polyadenomatosis (Wermer syndrome). The inhibitory action of the parathormone antagonist calcitonin on the exocrine functions of the intestinal tract, such as the acid secretion of the stomach and the enzyme secretion of the pancreas, have already given rise to some considerations and experiments relative to treatment. It is to be hoped that because of all the joint observations cited above there will be better intergration of research both from the aspect of gastro-enterology and endocrinology. This might hopefully elucidate some of the unresolved problems ranging from basic research to practical application.

Somatostatin: a potent inhibitor of ACTH-hypersecretion in adrenal insufficiency

Somatostatin (250 mug as a bolus i.v. and 250 mug as a 1-hr infusion) was administered to 5 patients with adrenal insufficiency of different origin. In each patient a sustained, progressive fall in plasma ACTH was observed during the infusion period. The mean maximal reduction in plasma ACTH was 43.8 +/- 5.9%. After cessation of the somatostatin infusion there was a rise of plasma ACTH to starting levels within 1/2 hour. These findings suggest that somatostatin is a potent inhibitor of ACTH secretion, however, only in a condition in which glucocorticoids are lacking.

Effects of somatostatin on exocrine and endocrine pancreatic function stimulated by intestinal hormones in man

To evaluate the action of somatostatin on exocrine and endocrine pancreatic function, synthetic somatostatin (GIF) was administered (intravenous bolus of 300 mug followed by a constant 60-minute infusion, 5 mug/min) to 17 normal subjects. The secretin-induced volume and total bicarbonate contents of the duodenal aspirate were not affected whereas the bicarbonate concentration was significantly diminished. GIF reduced decisively the pancreatic enzyme secretion stimulated by pure (99%) cholecystokinin-pancreozymin. After the GIF infusion was stopped, a significant rise in enzyme secretion was observed. The secretin-induced insulin release was almost completely suppressed. Because GIF can be extracted in large quantities from pancreas, these data suggest that somatostatin may play a physiological role in the regulation of the secretory processes of this organ. Furthermore, GIF may be a useful adjunct in the treatment of acute pancreatitis.

Hypoglycemia in diabetics

Hypoglycemia in diabetes can be divided into 1) spontaneous hypoglycemic reactions due to absolute or relative overproduction of endogenous insulin or some other blood glucose-lowering substance, as in islet cell adenoma or carcinoma, latent or protodiabetic conditions, (extrapancreatic) tumors and pituitary and/or adrenal disorders; and 2) hypoglycemia caused by exogenous, i.e. therapeutic, measures. The problem of hypoglycemia in insulin-treated diabetics is far from being solved. As revealed by continuous blood glucose monitoring, nocturnal hypoglycemic attacks frequently escape attention especially in juvenile diabetics. Circadian variations in peripheral glucose utilization, rather than changes in plasma insulin activity, are likely to be involved in this mechanism. At least, this was the conclusion drawn from studies carried out by means of a glucose-controlled insulin and glucose infusion system (GCIGIS) -or artificial pancreas-which delivers short-acting insulin and glucose on demand intravenously. Hypoglycemic reactions in patients being treated with oral anti-diabetic agents, on the other hand, should be regarded primarily as one of the side reactions intrinsic to the mechanism of action of some of these drugs, e.g. sulfonylureas, which act mainly via stimulation of secretion of endogenous insulin reserves not responding properly to postprandial blood glucose increments. In the case of glibenclamide, at least partial resensitization of the defective glucose receptor of the beta-cell also becomes operative. A higher incidence of a characteristic type of hypoglycemic reaction was observed soon after glibenclamide therapy was introduced. Better understanding of the drug and dissemination of the information about it to doctors and patients has reduced the number of hypoglycemic reactions caused by glibenclamide to the same proportions as for other sulfonylureas. Hypoglyoemia following therapeutic hypophysectomy retains its position as one of the main hazards of this heroic therapy.

Effect of lipids on insulin, growth hormone and exocrine pancreatic secretion in man

Influences of fat on release of insulin, growth hormone and pancreatic enzyme secretion were studied in 35 metabolically healthy subjects. A fat solution containing 40 g of soy bean oil was administered, I.V., orally and intraduodenally. In all cases there was a similar increase of insulin but the rise in serum insulin after oral or intraduodenal fat administration was not related to the changes in plasma free fatty acids, free glycerol and triglyceride levels. Blood surgar responded according to insulin secretion. The route of fat administration may possibly influence growth hormone secretion. Following intraduodenal fat administration volume and bicarbonate contents of the duodenal juice rose slightly whereas trypsin and bilirubin content increased considerably. These results suggest that insulin secretion after oral or intraduodenal administration of fat is influenced by intestinal factors. Cholecystokinin-pancroezymin and gastric inhibitory polypeptide are qualified to serve as such factors.

Extended somatostatin treatment of a patient with bleeding ulcer

The results of a 67 hour cyclic somatostatin continuous infusion in a patient with a bleeding ulcer are reported. The subject was a 65 year old male with very heavy gastrointestinal bleeding on the 9th postoperative day following a high BI-resection. Endoscopy revealed the bleeding to be caused by two residual ulcers in the area of the anastomosis. Somatostatin treatment led to an immediate cessation of the bleeding after 1 hour. Gastric secretion as well as gastrin, insulin and growth hormone levels were significantly inhibited by somatostatin. Endoscopy at the end of the treatment period showed two ulcers in the process of healing. The raised blood glucose levels caused by somatostatin were easily controlled with max. 14 IU cristalline insulin daily. Except for dryness in the mouth, no adverse side effects were apparent. There was no evidence from laboratory investigations of hemostatic defects or bleeding tendency in the patient.