Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to analyse further the pathophysiology of pentamidine effects on blood glucose regulation, the following experimental models were established in rats: impairment of the renal function, bile duct ligation, inhibition of the P450 cytochrome enzyme system. In otherwise intact rats, 7.5 mg/day pentamidine was well tolerated whereas doses of 15 mg/day induced severe, relapsing and eventually lethal hypoglycaemia within a few days. Induction of a renal insufficiency of graded severity by treatment with gentamycin, subtotal nephrectomy and total bilateral nephrectomy resulted in repetitive, severe (sometimes lethal) hypoglycaemia, alternating with hyperglycaemia, glucosuria and ketonuria in pentamidine-treated rats (7.5 mg/d). No long-standing insulin-dependent diabetes was observed. In the dysglycemic animals, plasma insulin levels were inappropriate to the concomitant glycaemia; no stimulation was obtained by i.v. glucose. Glucagon levels were higher than normal, suppressible by i.v. glucose, responsive to IV arginine and to hypoglycaemia. Dysglycemic events were more frequent and marked in the rats with the most severe renal functional derangement. They were more frequent in the rats treated with pentamidine mesylate than in those treated with the isethionate salt. Control uremic rats (free of pentamidine) remained euglycaemic. The islets of Langerhans displayed severe vascular congestion and degranulation and necrosis of the B cells, while the non B cells (and particularly the A cells) were intact. Exocrine pancreatitis was occasionally observed in the most severely uremic rats. In contrast with uremic rats, neither surgical ligation of choledocus, nor treatment by P450 cytochrome inhibitors (particularly ketoconazole) precipitated dysglycaemia in the pentamidine-treated rats. These experimental data: 1) strengthen the concept of inappropriate insulin release from pentamidine-lesioned islet B cells due to pentamidine accumulation; 2) indicate a predominant role for renal insufficiency in determining the accumulation of this drug; 3) emphasize the clinical importance of renal insufficiency as a risk factor for pentamidine-induced dysglycaemia. Association with ketoconazole does not appear to be a risk factor.
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PMID:Pentamidine-induced dysglycaemia: experimental models in the rat. 833 59

Antibodies to glutamic acid decarboxylase (anti-GAD) and pancreatic beta cell secretory function were measured in 39 consecutive Chinese patients with a clinical diagnosis of insulin-dependent diabetes mellitus (IDDM) (19 males, mean +/- SD age. 37 +/- 15 years; body mass index (BMI), 22 +/- 4 kg/m2; mean duration of disease, 6.7 +/- 5.6 years). IDDM was defined on the basis of acute symptoms with heavy ketonuria (> 3+) or ketoacidosis at diagnosis, or requirement for continuous insulin treatment within one year of diagnosis. Insulin deficiency was defined as a post-glucagon stimulated plasma C-peptide concentration < or = 0.6 nmol/l. Overall, anti-GAD antibodies were positive (> 18 units) in 23% (n = 9) of these patients. Of the 39 patients, 29 (74%) were insulin deficient and 10 (26%) were non-insulin deficient. Anti-GAD antibodies were positive in 31% of the insulin-deficient patients but in none of the non-insulin-deficient group. Insulin deficiency and anti-GAD positivity were associated with younger age, earlier age of clinical onset and lower BMI. There were independent negative relationships between levels of anti-GAD antibodies and blood pressure and a positive relationship between insulin dosage and albuminuria. This study emphasises the difficulty in differentiating clinically between IDDM and NIDDM in Chinese patients. Despite the acute presentation, these patients had variable pancreatic beta cell secretory function. The varying duration of disease may partly explain the low prevalence of positive anti-GAD antibodies in these patients, but seems unlikely to explain fully the difference from Caucasian IDDM patients.
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PMID:Pancreatic beta cell function and antibodies to glutamic acid decarboxylase (anti-GAD) in Chinese patients with clinical diagnosis of insulin-dependent diabetes mellitus. 880 79

We have performed clinical, in vitro biochemical, and genetic studies of a patient with severe insulin resistance, considerable growth restriction, and Rabson-Mendenhall syndrome (patient RM-3). The blood IGF-I level was undetectable in this patient, although the GH level was moderately decreased. During the postprandial period, glycemia, ketonuria, and plasma glucagon were very elevated despite high doses of exogenous insulin (glucose levels up to 30 mmol/L). In the postabsorptive state, blood glucose was normalized with small amounts of insulin; ketonuria, and glucagon levels were reduced but remained supranormal. Erythrocytes and cultured skin fibroblasts from the patient displayed a decrease in cell surface insulin receptors (IRs). The ability of physiologic concentrations of insulin to stimulate metabolic processes was altered in patient fibroblasts. Analysis of the IR gene by denaturing gradient gel electrophoresis and direct sequencing showed a homozygous missense mutation in exon 3, replacing Cys284 by Tyr in the alpha-subunit. In conclusion, marked primary insulin resistance was evidenced in patient cells as a result of a structural alteration in the IR alpha-subunit. The in vitro studies could not account alone for the in vivo metabolic alterations because glucose homeostasis varied considerably during the day in the patient.
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PMID:Major circadian variations of glucose homeostasis in a patient with Rabson-Mendenhall syndrome and primary insulin resistance due to a mutation (Cys284-->Tyr) in the insulin receptor alpha-subunit. 921 40

Medical records of 10 cats with transient clinical diabetes mellitus were reviewed. At the time diabetes was diagnosed, clinical signs included polyuria and polydipsia (10 cats), weight loss (8 cats), polyphagia (3 cats), lethargy (2 cats), and inappetence (1 cat). Mean (+/- SD) fasting blood glucose concentration was 454 +/- 121 mg/dL, mean blood glucose concentration during an 8-hour period (MBG/8 hours) was 378 +/- 72 mg/dL, and glycosuria and trace ketonuria were identified in 10 and 5 cats, respectively. Baseline serum insulin concentration was undetectable (6 cats) or within the reference range (4 cats) and serum insulin concentration did not increase after i.v. glucagon administration in any cat. Insulin-antagonistic drugs were being administered to 5 cats and concurrent disorders were identified in all cats. Management of diabetes included administration of glipizide (6 cats), insulin (3 cats), or both (1 cat), discontinuation of insulin-antagonistic drugs, and treatment of concurrent disorders. Insulin and glipizide treatment was discontinued 4-16 weeks (mean, 7 weeks) after the initial diagnosis of diabetes was confirmed. At the time treatment for diabetes was discontinued, clinical signs had resolved, mean fasting blood glucose concentration was 102 +/- 48 mg/dL, MBG/ 8 hours was 96 +/- 32 mg/dL, glycosuria and ketonuria were not identified in any cat, and concurrent disorders (except mild renal insufficiency in 1 cat) had resolved. Significant (P < .05) increases occurred in postglucagon serum insulin concentrations, insulin peak response, and total insulin secretion, compared with values obtained when clinical diabetes was diagnosed. Histologic abnormalities were identified in pancreatic islets of 5 cats in which pancreatic biopsies were obtained and included decreased number of islets (4 cats), islet amyloidosis (3 cats), and vacuolar degeneration of islet cells (3 cats). Mean beta cell density was significantly (P < .001) decreased in diabetic cats compared with control cats (1.4 +/- 0.7 versus 2.6 +/- 0.5%, respectively). Cells within islets stained positive for insulin, however, the number of insulin-staining cells per islet and the intensity of insulin staining were decreased in 5 and 2 cats, respectively. Clinical diabetes had not recurred in 1 cat after 6 years, in 4 cats lost to follow-up after 1.5, 1.5, 2.0, and 2.5 years, and in 2 cats that died 6 months and 5.5 years after clinical diabetes resolved. Clinical diabetes recurred in 3 cats after 6 months, 14 months, and 3.4 years, respectively. These findings suggest that cats with transient clinical diabetes have pancreatic islet pathology, including decreased beta cell density, and that treatment of diabetes and concurrent disorders results in improved beta cell function, reestablishment of euglycemia, and a transition from a clinical to subclinical diabetic state.
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PMID:Transient clinical diabetes mellitus in cats: 10 cases (1989-1991). 1005 60

Histological and immunohistochemical studies were carried out on the pancreas of twelve cattle of insulin-dependent diabetes mellitus (IDDM). They showed clinical signs such as persistent hyperglycemia, glycosuria and decreased glucose tolerance, and some cases accompanied with or without ketonuria. Histopathologically, eight cattle were diagnosed as chronic IDDM, while others were acute IDDM. The most characteristic lesions of the pancreas in chronic IDDM showed a decrease in the size and number of pancreatic islets, interlobular and interacinar fibrosis, mild lymphocytic insulitis, and vacuolation of a few islets. Almost all cells in the atrophied islets had a small amount of ungranulated cytoplasm. Immunohistochemical examination revealed that the atrophied islet cells did not react to anti-insulin antibody, but occasionally reacted to anti-glucagon or somatostatin antibodies. A few solitary islets with mild lymphocytic infiltration, necrotic islets with occasional calcification, and atrophied islets with mild fibrosis were also observed. A few islets consisted of many islet cells with vacuolated cytoplasm including a small number of insulin-positive granules. Accumulation of glycogen granules was occasionally observed in these islets. Islet fibrosis was due to the proliferation of collagen fibers reactive to both anti-collagen type I and type III antibodies. In acute IDDM, the major islets consisted of the cells with vacuolated cytoplasm indicating the degranulation of islet cells. These islets contained many islet cells with shrunken cytoplasm and karyorrhectic nuclei. Lymphocytic infiltration was frequently observed in the islets which consisted of many islet cells having karyorrhectic nuclei and vacuolated and severely degranulated cytoplasm. Immunohistochemically, islet cells with vacuolated cytoplasm had a small amount of insulin-positive granules, suggesting severe degranulation of beta-cells. An increase in acinar islet-cells and proliferation of ductal epithelial cells showing insulin-immunoreactivity were observed. Bovine IgG-immunoreactive islet cells were frequently seen in the vacuolated islets. In summary, pathological observations suggested that beta-cells were being destroyed by an inflammatory process which selectively affected the pancreatic islets. Lymphocytic insulitis and anti-bovine immunoreactive islet cells were thought to be the most significant changes in determining the etiology and pathogenesis of bovine IDDM, and suggested their role in anti-islet autoimmunity in this form of diabetes.
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PMID:Histopathological and immunohistochemical analysis of the endocrine and exocrine pancreas in twelve cattle with insulin-dependent diabetes mellitus (IDDM). 1045 4

Insulin deficiency and counterregulatory hormone excess are the basic process in the development of diabetic ketoacidosis (DKA). Somatostatin, which suppresses the secretion of glucagon and growth hormone, has been known to attenuate the rate of gluconeogesis and ketogenesis in insulin-dependent diabetes mellitus patients. However, the therapeutic efficacy of somatostatin has not been approved to be practical in the treatment of manifest DKA. To examine the additive effect of octreotide, the synthetic long-acting somatostatin analogue SMS 201-995, to conventional treatment of manifest DKA, we compared the correction time of acidosis, ketonuria, and hyperglycemia of patients treated with an intravenous infusion of low-dose insulin (4 units per hour) plus subcutaneous injection of octreotide (50 microg every 6 hours) by low-dose insulin alone. The correction time for hyperglycemia and acidosis did not show any difference between groups (p = 0.089, p = 0.82). However, the time for disappearance of ketonuria of the octreotide-treated group (38.0 +/- 32.0 h) was reduced significantly compared to other group (68.3 +/- 26.0 h) (p = 0.048). These results indicated that the addition of octreotide to conventional treatment of DKA might improve the correction of ketosis, but would not allow more rapid control of acidosis and hyperglycemia in manifest DKA.
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PMID:Effects of long-acting somatostatin analogue (Sandostatin) on manifest diabetic ketoacidosis. 1076 4

This paper describes a 6-year-old Simmental bull with diabetes mellitus. The animal was referred to our clinic because of severe weight loss and chronic indigestion. Clinical examination revealed markedly disturbed general condition, impaired forestomach function and polyuria. There was aciduria, glucosuria and ketonuria. The most important biochemical findings were severe hyperglycemia, markedly increased activities of hepatic enzymes and severe metabolic acidosis. Plasma concentrations of insulin, insulin-like growth factor-I, thyroxine and 3,5,3'-triiodothyronine were lower than normal, whereas those of glucagon were higher than normal. Based on these findings, a diagnosis (secondary) diabetes mellitus was made. The bull was slaughtered and histological examination revealed mixed cell pancreatitis with severe degeneration of islet cells. Immunohistochemical examination of the pancreas showed that very few insulin-, glucagon-, somatostatin- and pancreatic polypeptide, insulin-like growth factor-I and adrenomedullin-producing islet cells were present.
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PMID:[Diabetes mellitus caused by pancreatitis in a bull]. 1123 31

Hyperinsulinism, although rare, is the most common cause of persistent hyperinsulinaemic hypoglycaemia in infancy. Because of persistent hypoglycaemia, serious difficulties are encountered in the long term management of this condition. A male neonate, after an uncomplicated full-term pregnancy, had been admitted to another hospital with convulsions on the third post-natal day. Meningitis had been suspected at that time and treated with phenobarbital and he had been discharged from the hospital. At three-months old he was referred to our department for persistent convulsions and lethargy. His parents were of 1st degree consanguinity. His blood glucose level was found to be 24 mg/dl (1.33 mmol/L). Because of the dangerously high insulin level during hypoglycaemia (insulin/glucose > 0.3), the absence of ketonuria, and the need for a high dose of glucose infusion (> 15 mg/kg/min) to achieve normoglycaemia and a glycaemic response to glucagon despite the hypoglycaemia, a diagnosis of persistent hyperinsulinaemic hypoglycaemia of infancy was made. Since maximal doses of prednisone, glucagon, diazoxide, octreotide and high infusion of glucose were ineffective in achieving normoglycaemia, a subtotal (80%) pancreatectomy was done. Postoperatively intermittent hypoglycaemic episodes continued. These were controlled with low doses of octreotide. Histology revealed diffuse adenomatous hyperplasia (nesidoblastosis). The boy is now in the sixth post-operative month and developing normally.
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PMID:Persistent hyperinsulinaemic hypoglycaemia of infancy: case report. 1263 64

We report a new case of hereditary hepatic glycogen synthase (GS) deficiency (MIM 240600) in a French Canadian girl referred at 7 years of age for a family history of hyperlipidemia. Her initial evaluation incidentally revealed fasting hypoglycemia and ketonuria after a 10-hr fast with normal growth, development, and physical examination. Additional biochemical findings included fasting hypoalaninemia with elevated plasma branched chain amino acids and postprandial hyperlactatemia. Liver glycogen synthase activity was reduced. Unlike most other reported patients, we observed on three different occasions an increase in fasting plasma glucose levels after glucagon administration during episodes of hypoglycemia. At 13 years of age, her growth and intellect are normal; however, she still has hypoglycemia after 18 hr of fasting. From our patient's course and a review of the literature, we conclude: (A) Usual modes of presentation of GS deficiency are non-specific symptoms after overnight fasting (7/17), incidental findings (3/17), or positive family history (7/17); (B) Most patients maintain normal growth (8/11) and intellectual abilities (12/15); (C) Fasting hypoglycemia (17/17) and reduced liver glycogen content (9/9) are constant features; (D) Biochemical findings also include postprandial hyperlactatemia (13/13), fasting hyperketonemia (12/12), and fasting hypoalaninemia (8/9); (E) Glucagon response following fasting hypoglycemia is usually reduced or absent (7/8) but can be repeatedly present (1/8); (F) Liver steatosis is frequent (6/6). Although rare, GS deficiency results in a characteristic biochemical profile that, if recognized, should lead promptly to its diagnosis.
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PMID:Long-term follow-up of a new case of liver glycogen synthase deficiency. 1279 86

The aim of this study is to present the experience of applying hypoglycemia evaluation protocol. We performed a prospective study with 13 children with hypoglycemia symptoms at the Hospital of Clinicas of Porto Alegre, with range age 5.3+/-4.5 months and eight patients are female. The patients had been submitted to glucagon fasting test and blood glucose, lactate, pH, C peptide, insulin, fatty acids, TSH, GH, cortisol, and urine ketones were measured. Eight patients presented persistent hypoglycemia and five presented transitory hypoglycemia. The most frequent diagnosis was persistent hyperinsulinism. We suggest the use of a simple protocol for the evaluation of hypoglycemia, which contemplates the identifications of the main etiologies in children and facilitates the handling of these patients.
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PMID:[Childhood hypoglycemia: results of prospective evaluation protocols in children with up to 1 year of age]. 1820 92


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