The growth hormone clamp technique: inhibition of growth hormone release by growth hormone occurs independently of free fatty acids.

It has been suggested that growth hormone (GH) can inhibit its own release: in fact it has repeatedly been shown that an acute methionyl-GH (met-GH) infusion blocks the GH response to GH-releasing hormone (GHRH). However, met-GH infusions are accompanied by a significant increase of free fatty acids (FFA), which can block GH release. The aim of this study was to evaluate whether the inhibition of GH response to GHRH also occurs when lipolysis is pharmacologically blocked.

Combined therapy with glibenclamide and ultralente insulin in lean patients with NIDDM with secondary failure of sulfonylureas. Follow up at two years.

Nine lean diabetic patients with secondary failure of oral hypoglycemic agents and with a poor residual insulin release under treatment with glibenclamide (15 mg/day) entered a cross-over study, in which ultralente insulin was administered alone or in combination with glibenclamide (15 mg/day). Combined therapy was accompanied by increased serum free-insulin levels and was more effective than glibenclamide alone on daily blood glucose profile, on glycosylated haemoglobin (HbA1C) and on Beta-OH butyrate; in 6 patients a near normalization of blood glucose control (daily blood glucose levels less than 180 mg/dl) occurred. C peptide release, evaluated as daily profile and as response to i.

High heparin released platelet factor 4 in uncomplicated type 1 diabetes mellitus.

The role of platelet activation in diabetic microangiopathy is still controversial. We evaluated the degree of platelet activation in relation to vessel wall damage in three selected, well matched groups of subjects (10 healthy controls; 20 insulin dependent diabetic patients, 10 without microangiopathy and 10 with microangiopathy). We measured beta TG and PF4 plasma levels before and 5, 15 and 90 min after a heparin bolus i.

Effect of acipimox, a lipid lowering drug, on growth hormone (GH) response to GH-releasing hormone in normal subjects.

Growth hormone (GH) induces lipolysis and an increase of free fatty acids (FFA), and FFA inhibit the GH response to arginine and to GH-releasing hormone (GHRH). The aim of this study was to evaluate the effect of the pharmacologic blockade of lipolysis on the GH response to GHRH. Eleven normal men underwent a saline infusion starting at 09:00 h, after administration of placebo or 500 mg acipimox, an antilipolytic agent; at 13:00 h (0 min) they received GHRH, 50 micrograms iv The GH response to GHRH (0 to 120 min) was significantly higher in subjects pretreated with acipimox than in subjects pretreated with placebo.

Pharmacological interaction between tolbutamide and acetylsalicylic acid: study on insulin secretion in man.

This study has been planned to investigate some aspects of the interaction between acetylsalicylic acid (ASA) and tolbutamide on insulin secretion. In healthy subjects, oral administration of 3.2 g daily of ASA for 3 days significantly enhanced a) basal insulin levels (p less than 0.

Effects of intraperitoneal versus subcutaneous insulin administration on lipoprotein metabolism in type I diabetes.

In order to compare the effects of intraperitoneal (IP) versus subcutaneous (SC) insulin delivery on plasma lipoproteins, lipoprotein cholesterol, triglycerides, and very-low-density lipoprotein (VLDL) metabolism were compared in five type I diabetic patients while they were receiving continuous IP insulin (CIPII) or continuous subcutaneous insulin infusion (CSII). Each therapy regimen was of at least 1 month duration, and patients were treated in random order. Mean daily plasma insulin was lower on CIPII compared with CSII.

Isolation of the elusive pig islet.

This study describes a procedure for large scale isolation of swine islets. The reported results are from 15 consecutive isolations. The glands were removed from live animals with no warm ischemia, and the pancreata were digested by a modification of the automated method for human islet isolation.

Autoantibodies to GABA-ergic neurons and pancreatic beta cells in stiff-man syndrome.

Stiff-man syndrome is a rare disorder of the central nervous system of unknown pathogenesis. We have previously reported the presence of autoantibodies against glutamic acid decarboxylase (GAD) in a patient with stiff-man syndrome, epilepsy, and insulin-dependent diabetes mellitus. GAD is an enzyme selectively concentrated in neurons secreting the neurotransmitter gamma-aminobutyric acid (GABA) and in pancreatic beta cells.

[Possible correlations between protein-loosing nephropathy and obesity].

Nephrotic syndrome has been reported in obesity; its precise incidence in obese patients without diabetes mellitus and/or arterial hypertension is however unknown. Thirty-two obese subjects without complications were therefore assessed before and after weight loss, together with 18 healthy control subjects. Overnight albumin excretion rate (AER) was assessed using a RIA method (H.

The glucose clamp technique for the study of patients with hypoglycemia: insulin resistance as a feature of insulinoma.

Occurrence of hypoglycemia during a prolonged fasting, accompanied by inappropriately high serum insulin levels, is considered a reliable index of the presence of insulinoma. Previous in vitro studies on insulin receptors, and in vivo hyperinsulinemic clamps have shown that patients with insulinoma are insulin resistant. In the present study 10 patients with insulinoma, 6 patients with nontumoral (also called functional or reactive hypoglycemia) hypoglycemia and 6 normal subjects were fasted for 24 h and their blood glucose levels were maintained constant by means of a programmed glucose infusion (isoglycemic glucose clamp) delivered by an artificial pancreas (Biostator).

Selection of donors significantly improves pig islet isolation yield.

The purpose of the present study was to test the influence of donor age on islet isolation yield in swines. Large White pigs of 10 months (group 1, n = 10) and 2-3 years (group 2, n = 5) were used. A modification of the automated method for human islet isolation was used for pig islet separation.

Swine islet isolation and transplantation.

An isolation procedure for large scale isolation of swine islets is described. The results from 15 consecutive isolations are reported. The glands were excised from heart beating animals with no warm ischemia time.

Basal and norepinephrine-stimulated lipolysis in differently sized human isolated adipocytes: comparison of three modalities for results expression.

Lipolytic rate in basal conditions and after adrenergic stimulation with norepinephrine (NE, 8.87 microM) from suspensions of differently sized human adipocytes has been tested. Adipocytes were intra surgically provide for obese (OB) and normal-weight (NW) individuals.

Platelet sensitivity in vitro to the prostacyclin analogue iloprost in diabetic patients.

Iloprost is a chemically stable analogue of prostacyclin, with similar vasodilator and anti-platelet actions. Platelet sensitivity to the inhibitory action of Iloprost has been tested in vitro. Platelet-rich plasma from six healthy subjects and from six patients with type 1 diabetes mellitus was incubated with different concentrations of Iloprost, and then stimulated with ADP (at threshold aggregating concentration) and collagen 4 micrograms/ml.

Intranasal glucagon as remedy for hypoglycemia. Studies in healthy subjects and type I diabetic patients.

Intranasal glucagon can raise blood glucose levels in healthy subjects. The aims of this study were to 1) compare the hyperglycemic effect of intranasal and intramuscular glucagon in healthy subjects and type I (insulin-dependent) diabetes patients during euglycemic conditions and 2) test the efficacy of intranasal and intramuscular glucagon in counteracting hypoglycemic episodes in insulin-treated diabetic patients. Intranasal glucagon raised blood glucose levels in both healthy subjects and type I diabetic patients, the effect of intramuscular glucagon being similar for the first 30 min and higher thereafter.

[MR (1.5 T) in the evaluation of pancreas transplant rejection].

Graft rejection is the major cause of graft loss following pancreatic transplantation. Early detection of the rejection process is of great importance towards planning effective treatment when transplant recipients present with aspecific clinical findings suggesting rejection. Up to date, the demonstration of pancreatic transplant rejection has been attempted with nuclear medicine and sonography (US).

Mental arithmetic stress as a test for evaluation of diabetic sympathetic autonomic neuropathy.

The effects of a 1-min mental arithmetic stress test on heart rate change were studied in 72 Type 1 diabetic patients, 36 without and 36 with diabetic autonomic neuropathy (mean age 33 and 44 yr, respectively), and in 80 matched normal subjects. Variation in hand skin temperature was also recorded in 25 normal subjects and 30 diabetic patients without and 32 with autonomic neuropathy. While mental arithmetic rapidly reduced skin temperature of normal volunteers and of patients without autonomic neuropathy, no effect was found in autonomic neuropath (a drop of 0.