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Biomedical subjects

M Ziegler

Publications and source records attributed to M Ziegler.

At least 433 records · Page 24Linked to original sources
PubMed1976

Investigations on isolated islets of Langerhans in vitro. XIV. Insulin secretion and insulin stores of cultivated islets from sand rats (Psammomys obesus): investigations of glucose-dose response.

Release of immunoreactive insulin activity (IRI) and biological insulin like activity (ILA) from collagenase isolated pancreatic islets of sand rats (Psammomys obesus) maintained on a vegetable diet were examined at 60 min and 24-48 h intervals under culture conditions at 1.0 and 15.6 mM glucose. The glucose-insulin dose response curves for sand rats after 60 min incubation were compared with those after 24 or 48 h of incubation. The pancreatic islets responded to 5mM glucose with a high insulin release especially under culture conditions. A drastic depletion of stored insulin in the islets cultivated for 2 days at 5 or 15 mM glucose is accompanied by a continuous diminution of the glucose-induced insulin release with the prolongation of cultivation up to one week.

Animals↗
PubMed1976

The mechanism of insulin secretion after oral glucose administration. VIII. Pancreatic juice insulin excretion after glucose loading and meal ingestion in normal and vagotomized dogs.

On pancreatic fistula dogs, in the pancreatic juice, immunoreactive insulin has been identified. Insulin excretion is shown to be inhibited by an intravenous glucose load and to be stimulated in a biphasic manner by an oral glucose load or by ingestion of mashed meat. Insulin excretion is reduced 2 months after bilateral truncular vagotomy and the reaction to both oral stimuli is abolished. -- There is no statistical correlation between pancreatic juice insulin and blood glucose, plasma IRI, or plasma amino nitrogen concentrations. Single extrainsular B-cells shown by histologic examination are suggested to be the source of pancreatic juice insulin. Compared to insulin secreted into the portal blood flow, insulin in the pancreatic juice amounts to only 0.1--0.2% of the daily secretory rate of the islets of Langerhans.

Administration, Oral↗
PubMed1976

[Immunhistochemical investigations for evidence of insulin, glucagon and gastrin in the islets of Langerhans of Wistar rats during the development (author's transl)].

Insulin, glucagon and gastrin were investigated immunohistochemically in the islets of Langerhans in 14, 15, 17, 18 and 20 days old embryos, in newborn, 2, 5, 10, 20 and 30 days old and adult Wistar rats. The results were documented in series of microphotos. By means of the indirected immunofluorescence technique the insulin and glucagon were observed from the 18th day of the prenatal development in the B- resp. A-cells of the islets. Than the intensity of the fluorescence shows a continual increase during the development. In the islets cells of the developing stages and adult rats can't immunohistochemically evidenced the gastrin. The important results were discussed from the standpoint of the development physiology.

Animals↗
PubMed1976

Insulin kinetic, glucose tolerance, and lipid metabolism in genetically spontaneous-hypertensive rats.

Genetically spontaneous hypertension in rats (SHR) showed a significant rise not only in systolic blood pressure in the early age groups, but also, from the 8th week of life onward, in diastolic blood pressure together with a rise in heart rates, when compared with control rats. Following an i.p. glucose injection a disturbed glucose tolerance, increased insulin level and a reduction in plasma triglycerides and cholesterol occurred. These findings in SHR allow to draw interesting analogous conclusions as to the protodiabetic disturbances in carbohydrate metabolism accompanied by insulin enhancement after glucose and diminished glucose- and increased lipogenetic effects, which had been demonstrated by R. BAUMANN et al. in 58% of all studied cases of juvenile human hypertension (Stage I and Stage II, NITSCHKOFF and R. BAUMANN), in which possibly hereditary factors may be involved.

Animals↗
PubMed1975

Paradoxical glucagon response after stimulation with glucose and arginine in isolated pancreatic sand rat islets.

Isolated pancreatic islets of normoglycemic sand rats do not respond to 2.5 mM glucose with an enhanced glucagon secretion, which could be observed in normal Wistar rats. Arginine stimulates glucagon release in the presence of 2.5 mM glucose in Wistar rats as well as in sand rats. The secretion pattern is not caused by insulin deficiency since sand rat islets are characterized by an increased insulin secretion rate in vitro. This paradoxical glucagon secretion is not caused by a changed glucagon content but might be related to this species which is able to develop a diabetic syndrome spontaneously.

Animals↗
PubMed1975

[Stress incontinence in the woman (author's transl)].

The morphology and function of the urethrovesical junction are described to give some understanding of the pathogenesis and therapy of female stress incontinence. Conservative procedures can only be helpful in stage-1 stress incontinence, whereas in stage 2 surgical treatment provides excellent results.

Adrenergic beta-Antagonists↗
PubMed1975

[Comparison between the oral glucose tolerance test and the glucose infusion test in the characterization of protodiabetes].

Within 3 days the 2-hour glucose infusion test (GIT) and the 50gm oral glucose tolerance test (oGTT) were performed in 113 normal weight and 33 obese persons suspected to protodiabetes and in 14 control subjects respectively. The results are compared with criteria from a group of healthy persons without any heredity of diabetes worked out in our laboratory. In about 66 per cent of the investigated subjects a concordance between both tests could observed in carbohydrate tolerance. Abnormal results were found more frequently after the oral glucose application. From these finding it was concluded a higher sensitivity of the oGTT. On the other hand followup studies of the disagreed diagnosis have shown that in 91 per cent the test results of the GIT were reproduced. The insulin secretion pattern agreed in 70 per cent between both tests. Whereas the insulin secretion pattern during the oGTT does not allowed to differ between the groups using the glucose infusion test we were able to observe a significant diminished hormone release in the initial as well as in the late phases, if the carbohydrate tolerance was pathologically. Summarizing the results we concluded that the GIT is characterized by a good reproducibility and a higher diagnostic importance than the 50 gm oGTT.

Administration, Oral↗
PubMed1975

Effect of glucose infusion on venous blood levels of immunoreactive proinsulin activity, insulin activity and fat parameters in healthy and protodiabetic subjects.

Concentrations of immunoreactive insulin activity (IRI) and proinsulin activity (IRP), blood glucose, free fatty acids (FFA), glycerol, cholesterol, triglycerides were analyzed in 140 subjects suspect of protodiabetes and 50 healthy persons before, during and after a glucose infusion test (GIT). The protodiabetic subjects were classified into normweight, overweight, obese, hyperlipemic groups with diet or with Regadrin therapy and each of them subdivided into such with normal and such with pathological carbohydrate tolerance. Norm- and overweight subjects with asymptomatic diabetes were characterized by a significant reduction of insulin secretion during both phases. Obese patients with or without hyperlipoproteinemia demonstrated an increased IRI reaction during the late phase of secretion. Carbohydrate intolerance was associated with an enhancement of basal triglyceride levels and a reduced depression of glycerol and FFA during the GIT. There were no differences in fasting or reactive IRP concentrations between healthy and protodiabetic subjects with normal carbohydrate tolerance. In asymptomatic diabetes the IRP levels were increased during the late secretion phase, but the percentage of IRP in total IRI was normal or--in existing high response--significantly reduced in comparison to norm response. The results do not support an enhanced IRP secretion as the cause of carbohydrate intolerance.

Adult↗
PubMed1975

Determination of total insulin (TIRI) in plasma of insulin-treated diabetics and newborn infants of insulin-treated diabetic mothers.

Plasma of insulin-treated diabetics and of newborn infants of insulin-treated diabetic mothers contains insulin antibodies which invalidates the radioimmunoassay of insulin. Therefore, the endogenous insulin antibody complex must be splitted at a pH lower than 5 and the total IRI (TIRI) is separated by ethanol extraction. It was investigated the recovery rate in dependence upon plasma volume used for extraction. By reduction of used plasma volume from 500 to 200 mul per extraction the recovery rate was increased from 65.1 +/- 8.4 to 88.3 +/- 4.2% (mean +/- SEM). The low plasma volume of 200 mul for TIRI extraction made it possible to determine TIRI during glucose loads of newborn infants. To eliminate different conditions of incubation for standard and unknown plasma samples the TIRI levels were computed by means of so-called "extracted" standard curve, obtained with extracted insulin from standard insulin dilution in insulin-free pooled human plasma. Using the described method a temporary regeneration of insulin secretion of a newly diagnosed juvenile diabetic after insulin treatment could be shown. In contrast to newborn infants of healthy mothers a biphasic/insulin release was found during the intravenous glucose loads in newborn infants of insulin-treated diabetic mothers.

Adult↗
PubMed1975

[In vitro studies on the islands of Langerhans. XI. Insulin secretion and content of isolated islands of Langerhans in the Wistar rat under short term incubation and under organ culture conditions].

Insulin (IRI) secretion pattern of collagenase isolated islets from Wistar rats were investigated in a batch type incubation (60 min) and under organ culture conditions (up to 7 days) with different concentrations of glucose as stimulus. The B-cell response within 60 min of incubation was determined in Krebs-Ringer bicarbonate buffer with 1 mg/ml bovine serum albumin and 16 mM HEPES (KRB-HEPES) and compared with the hormone release in a culture medium (TC 199) containing 10% calf serum. Additionally the insulin content of islets before and after 7 days of culture was assayed radioimmunologically. In the presence of culture medium the insulin secretion was enhanced by 5.8 mM glucose whereas this glucose concentration does not stimulate the insulin secretion in KRB-HEPES. During organ culture the insulin secretion was identical in media with 1.0 and 5.8 mM glucose, respectively, but 15 mM glucose raised the hormon output more than 10-fold. The insulin content of islets, cultured for 7 days was decreased in the presence of 15 mM glucose up to 30% and in the presence of 5.8 mM glucose up to 13% of that of islets after isolation. The recovery rate of insulin calculated as the sum of secretion and content after cultivation at 15 mM glucose was higher than 100%, whereas the experiments in the presence of 1.0-5.8 mM glucose are characterized by a recovery rate of 25%. The results are discussed in connection with a altered intracellular breakdown of insulin in the B-cells.

Animals↗