In vitro metabolism of glucose-1-(14)C by adipose tissue into (14)CO(2) and total (14)C lipids in rat and man was compared employing both adipose tissue segments and isolated fat cells prepared from the same donor. In the rat, the basal glucose metabolism and response to insulin decreased with increasing body weight for both adipose tissue segments and isolated cells. Regardless of age, the isolated cells exhibited a persistently higher metabolic activity. Of the parameters selected, conversion to CO(2) was more pronounced than that to lipid.In contrast to the rat, in man adipose tissue segments were more active than isolated cells. In four subjects, the effect of 6, 50, and 400 muU/ml of insulin was analyzed on conversion of glucose-1-carbon to CO(2), long chain fatty acids, and glycerides by adipose tissue segments only. In 17 subjects, glucose oxidation and lipid synthesis by adipose tissue segments and isolated fat cells were measured and showed a definite response to physiological doses of crystalline pork insulin. There was, however, an age dependency, and consistent effects were obtained with 6 muU/ml in children and 50 muU/ml in adults. The responsiveness of human adipose tissue to exogenous insulin in concentrations comparable to those detected in blood reemphasizes the importance of adipose tissue as a major site for fatty acid synthesis.

Journal Article↗

PubMed1967

In vitro studies of insulin inactivation with reference to erythroblastosis fetalis.

Explore the source record for details and available documents.

Adipose Tissue↗

PubMedDate not supplied

Primary hyperlipoproteinemias as risk factors in peripheral artery disease documented by arteriography.

In a controlled study on 121 patients with peripheral vascular disease (PVD) (75 patients with primary hyperlipoproteinemia, 15 diabetics, 31 patients without metabolic disease) the relationship between risk factors (hyperlipoproteinemia, obesity, hypertension, abnormal glucose tolerance, smoking) and the degree and localisation of sclerotic lesions was investigated by angiography. The degree was directly related in all patients to the number of risk factors, in Type IIa to cholesterol levels, in diabetics and Type IV with abnormal glucose tolerance to age. The latter patients were 5-10 years older than patients with Type IIa and showed 2 or more additional risk factors. The sclerotic lesions affected in Type IIa, less in Type IIb, predominately the pelvic vessels. Diabetics and Type IV patients showed a distal arterial involvement. The difference was significant. The degree of sclerotic lesions in arteries of the pelvis and the distal lower limb was positively correlated with the cholesterol-triglyceride ratio. Smoking aggravated the pelvic lesions in Type IV. Hypertension lead to more pronounced lesions of the distal lower limb in Type II. S-shaped tortuosities of the big vessels were shown to be typical, independent of localisation or degree.

Age Factors↗

PubMedDate not supplied

The epidemiology of diabetic neuropathy. Diabetic Cardiovascular Autonomic Neuropathy Multicenter Study Group.

Although neuropathy has long been recognized as a complication of diabetes, the impact of this condition has not been adequately established. The prevalence of diabetic neuropathy is virtually unknown because the published studies differ considerably with regard to definition, method of assessment, and patient selection. Furthermore, the determination of prevalence has been hampered by the fact that there is no generally accepted classification of the variety of manifestations of diabetic neuropathy. The introduction of new sensitive diagnostic methods aids in the detection of less severe stages of neuropathy, as compared with clinically based assessment, and renders the disease more prevalent. The prevalence of diabetic neuropathy in the few reported population-based studies was approximately 30%. We have evaluated the prevalence of cardiovascular autonomic neuropathy in a group of approximately 1000 diabetic patients randomly included from 21 hospitals in Germany, Austria, and Switzerland. The results of this study and those of a prospective study on the natural history of neural dysfunction during the first 5 years after diagnosis of type 1 diabetes will be presented.

Adolescent↗

PubMedDate not supplied

Classical conditioning of insulin effects in healthy humans.

OBJECTIVE: Classical conditioning of insulin effects was examined in healthy humans using a placebo-controlled design. This study examined whether subjects who experienced a conditioned stimulus (CS) paired with insulin in the acquisition phase of a conditioning protocol would show a conditioned decrease of blood glucose when receiving the CS with a placebo injection in the test phase. METHODS: Twenty healthy male students were assigned either to group 1, which received insulin (0.035 IU/kg i.v.), or to group 2, which received i.v. saline on 4 consecutive days (acquisition). On day 5 (test), both groups were injected with saline. The CS was an olfactory stimulus. Blood glucose, serum insulin, plasma glucagon, plasma catecholamines, serum cortisol, and symptoms were repeatedly measured during each session. RESULTS: In the test phase, group 1 reacted with a significantly larger decrease of blood glucose after presentation of the CS than group 2. Within group 1, a larger conditioned blood glucose decrease was associated with features that enhance classical conditioning (ie, intensity of the unconditioned response and intensity of the CS). Furthermore, in group 1, there was an increase of baseline insulin from day 1 to day 5 and a tendency for insulin reduction after CS presentation. Groups also tended to differ in cortisol and neuroglycopenic symptoms after CS presentation. CONCLUSIONS: Conditioned effects in blood glucose are in accordance with the predictions. As a result of the exploratory analyses, our data also provide hints about conditioned changes in insulin, counterregulatory hormones, and symptoms.

Adult↗

PubMedDate not supplied

Differential effects of near-normoglycaemia for 4 years on somatic nerve dysfunction and heart rate variation in type 1 diabetic patients.

To evaluate the long-term effects of near-normoglycaemia on somatosensory and autonomic nerve dysfunction, 55 poorly controlled Type 1 diabetic patients were allocated to intensified insulin treatment using continuous subcutaneous insulin infusion or multiple insulin injections and were studied prospectively for 48 months. They were divided into three groups according to their mean HbA1 levels during the study. Group 1 (n = 19) had mean HbA1 during months 3-48 in the normal range of less than 7.8% (near-normoglycaemic control), Group 2 (n = 18) showed moderately elevated mean HbA1 between 7.8 and 8.5% (satisfactory control), and Group 3 (n = 18) had clearly elevated mean HbA1 of greater than or equal to 8.6% (poor control). In the three groups studied, the changes in nerve conduction over baseline in the median and peroneal motor nerves as well as median and ulnar sensory nerves after 4 years were inversely related to the mean HbA1 levels of months 3-48 (all p less than 0.05). No significant associations with mean HbA1 were noted for the ulnar motor and sural sensory nerve conduction, vibration perception threshold, and heart rate variation. The percentages of patients with neuropathic symptoms decreased from 32 to 14% in Group 1, remained fairly constant in Group 2, and increased from 41 to 73% in Group 3 after 48 months when compared to baseline (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMedDate not supplied

[Spontaneous hypoglycemia caused by extrapancreatic tumor].

Explore the source record for details and available documents.

Aged↗