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)

Since no data are available concerning thyroid hormone levels in Snell dwarf mice from birth on, a cross-sectional study was performed of L-thyroxine (T4) and L-triiodothyronine (T3) levels in blood or serum as a function of age of several litters, starting at birth. In normal Snell mice T4 levels in blood and serum are changing with age. T4 increases during the first 2 weeks of age and declines thereafter, until adult levels of about 50 nmol/l are reached at 21 days of age. Serum T3 values are in the range of 2-3 nmol/l. They do not show such an age-related pattern. From birth on in each litter there was a clear separation between animals with low T4 levels in blood and the others. This separation was possible at all subsequent days until 9 days of age, when dwarfs can be recognized by eye. Above that age the low T4 values were associated with dwarfism. This suggests that dwarfs are hypothyroid already at birth. Serum T3 in dwarfs falls below the normal range only after 4 weeks of age, resulting in a lower T4/T3 ratio than normal. The half life time of exogenous T4 in serum of dwarfs is in the range of 13-18 h and not different from normal. For T3 t1/2 is 9.5-11.1 h. Dwarf mice become euthyroid by treatment with 0.1 microgram T4 per day. 1 microgram T4 was needed to reach a physiological level of T3. These data suggest that the peripheral conversion of T4 to T3 is slower in dwarfs than in normals. Treatment with hGH, prolactin, glucagon, insulin, testosterone and oestradiol had no influence on serum T4. As expected TSH was stimulatory. Similar results were obtained for serum T3, with the exception of prolactin which caused slightly increased levels of serum T3.
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PMID:Thyroxine and triiodothyronine levels in Snell mice. 640 74

The increase in protein adsorption by charcoal as ionic strength increases (salting-out adsorption), was used to separate the bound and free fractions of glucagon, insulin, hGH, hLH and hPRL in the radioimmunoassay. The hormones were labelled with 125I and to express the immunocomplex, gamma-globulin was labelled with 125I. The charcoal used to produce the separation was suspended in magnesium sulfate 3 M (charcoal-SO4Mg). The optimum amount of charcoal and the final concentration of magnesium sulfate determined for each hormone were: glucagon (charcoal 5 mg/tube, 0.125 M); insulin (charcoal 5 mg/tube, 0.131 M); hGH (charcoal 40 mg/tube, 0. 447 M); hLH (charcoal 40 mg/tube, 0.447 M) and hPRL (charcoal 60 mg/tube, 0.321 M). The serum concentration was 1/20 for all hormones, excepting glucagon, where 1/10 was used. The stability of the immunocomplex was studied and it was shown that, under suitable conditions, increased ionic strength does not cause the dissociation of the bound fraction.
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PMID:Increase of ionic strength for charcoal separation of B/F fractions in radioimmunoassays. 676 10

The phenomenon of clinical improvement of diabetes mellitus after occurrence of pituitary insufficiency has been reported occasionally in the medical literature, as a human counterpart of Houssay's experiment with hypophysectomized diabetic animals. We report the case of a 76-year-old woman who developed diabetes in 1928, at the age of 14, and was treated with low doses of insulin. At the age of 29, during the 7th month of her second pregnancy, she suddenly developed severe headaches and soon afterwards an intense polyuria which subsided under treatment with posterior pituitary extract. Her pregnancy followed to term but uterine stimulants had to be used at delivery because of lack of contractions. She was unable to nurse her baby and a permanent amenorrhea ensued. She continued using the posterior pituitary powder for several years, after which she discontinued it without adverse effects. The dose of insulin was decreased gradually until its replacement by chloropropamide in 1967 and glibenclamide in 1970. The present dose of glibenclamide is 2.5 mg daily, on which she has occasional mild hypoglycemic reactions. When the medication was discontinued for 5 days glycemia rose to 450 mg/dl but responded immediately to 2.5 mg of the drug with a mild hypoglycemia. She never required thyroid hormone therapy. Glucocorticoid substitution was instituted recently because of evidence of mild adrenocortical insufficiency. Basal hormone levels were normal for thyroxin, thyrotropin, FSH, LH, prolactin, hGH and cortisol; the responses to pituitary stimulation with TRH and LHRH were subnormal or nil. Cortisol stimulation with ACTH was normal. Insulin levels rose moderately after stimulation with glucagon, and with glibenclamide, with simultaneous marked decrease in glycemia.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Houssay's phenomenon in man]. 820 16

Physiologically, the action of insulin on carbohydrate and lipid metabolism is opposed by several hormones, including glucocorticoids, glucagon, catecholamines, and pituitary GH. Perhaps least is known about the mechanism(s) involved in the antiinsulin action of GH. Since the generation of diacylglycerol (DAG) appears to be an early event in the insulin-signaling cascade, it was of interest to determine whether GH would interfere with this effect of insulin. Experiments were conducted to determine whether insulin would stimulate the generation of DAG in adipocytes of the obese (ob/ob) mouse, and whether this response could be blocked by the diabetogenic GH derivative S-carboxymethylated human GH (RCM-hGH). Isolated adipocytes of the ob/ob mouse were used for these studies, because unlike normal rodents, the ob/ob mouse responds predictably to the antiinsulin action of GH. Insulin produced a rapid biphasic increase in the amount of DAG in a crude membrane fraction of the adipocytes. The first peak in DAG mass occurred within 5 min of exposure of the cells to insulin, and the second peak occurred after 30 min. The first peak in DAG mass did not occur in adipocytes that had been incubated with pertussis toxin before exposure to insulin. Also, adipocytes isolated from ob/ob mice that had been treated with RCM-hGH failed to respond to insulin with an increase in DAG mass. RCM-hGH blocked both the first and second insulin-induced peaks in DAG mass within 6 h of its administration. This is the time at which ob/ob mouse adipocytes exhibit increased insulin resistance in response to RCM-hGH. Neither exposure to insulin nor treatment with RCM-hGH had any appreciable effect on the fatty acid composition of the DAG present in the adipocyte membranes. These findings are compatible with the idea that GH produces some defect in the insulin-signaling cascade that is proximal to the events that result in the generation of DAG in the adipocyte.
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PMID:The stimulatory effect of insulin on diacylglycerol generation in adipocyte membranes from ob/ob mice is impaired by growth hormone. 846 67

GH, in clinical practice, is determined by RIA, but RIA estimates may not accurately reflect serum GH bioactivity. The available measures of GH bioactivity lack either sensitivity, specificity, or a physiologically relevant end point. The objective of this research was to develop a physiologically relevant GH bioassay which would not only measure the bioactivity of purified GH preparations, but would also have sufficient sensitivity to measure GH bioactivity in human serum. The method consisted of incubating murine 3T3-F442A adipocytes in serum-free medium containing BSA, 14C-glucose, and increasing concentrations of GH or test materials for 24 h, followed by measurement of conversion of glucose to lipid. Interference by nonspecific serum factors was reduced by the addition of 10 micrograms/liter insulin, 25 nM dexamethasone, and 37 nM estradiol to the medium. In the presence of 10 micrograms/liter insulin, 50 micrograms/liter insulin-like growth factor-1 did not alter the ability of GH to suppress lipid accumulation. Epinephrine and glucagon could suppress lipid accumulation but only at concentrations greatly in excess of the physiological range in serum. Twenty two thousand dalton hGH produced dose-dependent suppression of lipid accumulation which was linear between 0.625 and 10 micrograms/liter (r = 0.926; P = 0.0001) with a half-maximal response of 3.0 +/- 0.2 micrograms/liter (n = six experiments). The intra- and interassay coefficients of variation were 7% and 19%, respectively. The assay was specific for GH since addition of human PRL produced suppression of lipid accumulation only at concentrations where contamination of the preparation by GH became a significant factor. ACTH also suppressed lipid accumulation but only at doses of 1000 micrograms/liter or greater. Human placental lactogen and hLH, hFSH, and hTSH did not cross-react with GH in this assay. Addition of human serum did not alter the slope of ED50 of the GH dose-response curve. Pools of serum from prepubertal and pubertal boys and girls, subjects treated with arginine or insulin, a diabetic girl, and a boy with gigantism who had a serum GH content of 80 micrograms/liter by RIA and 40 micrograms/liter by bioassay, produced dose response curves parallel to that of the GH standard curve. Serum from patients with hypopituitarism did not produce significant suppression of lipid accumulation in any assay. Recovery of 5 micrograms/liter GH added to human serum was 94%. Twenty thousand dalton GH also suppressed lipid accumulation in this assay, but was 2-fold less potent than 22,000 dalton GH.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Bioactivity of human growth hormone in serum: validation of an in vitro bioassay. 847 57

Proteins that bind growth hormone (GHBP) have been identified in the blood of many mammalian and avian species, but not in reptilian species. We carried out binding studies with the serum of turtles using chromatographic techniques as well as the dextran-charcoal separation method. As in other species, we found at least two different GHBPs: one with high MW and low affinity and the other with lower MW and higher affinity. The high affinity GHBP was partially purified using gel filtration and affinity chromatography, reaching a degree of purification of 11,000 times (0.17 nmol/g of serum protein in the serum vs 1900 nmol/g protein in the purified material). When the high affinity GHBP was characterized, it was found to have a dissociation constant (Kd: 2.6 +/- 0.7 nM) similar to those described for mouse or rat, but lower than those for chicken, rabbit or man. The binding capacity (Bmax) was 120 +/- 43 fmoles/mg of protein, which can be also expressed as 1.08 +/- 0.38 pmol/ml of serum. A preliminary MW estimation of 50-60 kDa was obtained for turtle higher affinity GHBP. The specificity of this high affinity GHBP is somatogenic, since bovine GH competes as well as human GH for 125I-hGH bound to binding protein, while ovine PRL competes only partially and with low affinity. Unrelated hormones, as insulin and glucagon, can not displace the 125I-hGH bound to turtle GHBP. A very important seasonal variation in turtle GHBP activity was observed: maximum binding was found in November (springtime), followed by a continuous decline over March and May.
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PMID:Identification and initial characterization of serum growth hormone binding protein in the turtle Chrysemys dorbigni. 925 1

The effect of 7 day continuous subcutaneous infusion of octreotide (200 microg day(-1)) was evaluated in seven insulin-pump treated Type 1 diabetic patients (age 43+/-1.5 year; BMI 25.1+/-0.7 kg m(-2); HbA(1c) 7.4+/-0.3%). A 24-h metabolic and hormonal profile, and a euglycaemic hyperinsulinaemic clamp (0.25, 0.5, 1.0 mg kg(-1) min(-1)), with [3H]glucose infusion and indirect calorimetry, were performed before and after a 7-day octreotide infusion. Mean 24-h plasma glucose was similar before and after octreotide (9.7+/-0.8 vs. 9.1+/-1.0 mmol l(-1)) but insulin requirement dropped by 45% (49+/-4 vs. 27+/-2 U day(-1); P<0.01). Both 24-h plasma hGH and glucagon were suppressed by octreotide (1.85+/-0.35 vs. 0.52+/-0.04 microg l(-1), and 117+/-23 vs. 102+/-14 ng l(-1), respectively). Glucose utilisation increased after octreotide (insulin 0.5 mU kg(-1) min(-1) clamp 3.09+/-0.23 vs. 4.19+/-0.19 mg kg(-1) min(-1); 1 mU kg(-1) min(-1) clamp 5.64+/-0.61 vs. 7.93+/-0.57 mg kg(-1) min(-1); both P<0.05) and endogenous glucose production was similarly suppressed. Glucose oxidation was not affected by octreotide, while the improvement in glucose storage (insulin 1.0 mU kg(-1) min(-1) clamp 3.89+/-0.60 vs. 5.64+/-0.67 mg kg(-1) min(-1), P<0.05) entirely accounted for the increase in glucose disposal. Endogenous glucose production was more effectively suppressed at the two lower insulin infusion rates (P>0.05). Energy expenditure declined after octreotide. Continuous subcutaneous octreotide infusion suppresses counterregulatory hormones, increases insulin-mediated glucose metabolism by enhancing glucose storage, and reduces energy expenditure. These results support a role for counterregulatory hormones in the genesis of insulin resistance and the catabolic state of Type 1 diabetes.
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PMID:Combination of continuous subcutaneous infusion of insulin and octreotide in Type 1 diabetic patients. 1116 89

The glucagon-like peptides (GLPs) are synthesized and secreted in a nutrient-dependent manner in rodents; however, the factors regulating human GLP-1 and GLP-2 biosynthesis remain unclear. To understand how nutrients regulate human proglucagon gene expression, we studied the expression of a human proglucagon promoter-growth hormone (GH) transgene in 1.6 human glucagon-GH transgenic mice. Fasting-refeeding significantly decreased and increased the levels of circulating mouse insulin and transgene-derived hGH (P < 0.05 fasting vs. refeeding) and decreased and upregulated, respectively, the levels of endogenous mouse proglucagon RNA in the ileum but not in the jejunum or colon. High-fiber feeding significantly increased the levels of glucose-stimulated circulating hGH and upregulated levels of mouse intestinal proglucagon gene expression in the jejunum, ileum, and colon (P < 0.05, 0 vs. 30% fiber diet). In contrast, neither fasting-refeeding nor a high-fiber diet upregulated the expression of the human proglucagon promoter-hGH transgene. These findings demonstrate that human proglucagon gene regulatory sequences specifying tissue-specific expression in gut endocrine cells are not sufficient for recognition of energy-derived signals regulating murine glucagon gene expression in enteroendocrine cells in vivo.
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PMID:Human glucagon gene promoter sequences regulating tissue-specific versus nutrient-regulated gene expression. 1174 36

Cerebral magnetic resonance imaging findings are of great value for the diagnosis of nonacquired GH deficiency (GHD), and ectopic posterior pituitary hyperintense signal (EPPHS) is a sensitive and specific indicator of hypopituitarism. It has been suggested that patients with childhood-onset GHD and EPPHS do not require additional investigation of GH secretion and should not be retested when adult height is achieved. This recommendation has never been validated through a systematic study. This study aimed to characterize the anterior pituitary function status of patients with EPPHS treated for GHD during childhood after completion of GH therapy when adult height had been achieved. Patients (n = 18; 15 males and three females) with childhood-onset GHD associated with ectopic neurohypophysis were treated with hGH (0.20 +/- 0.05 mg/kg.wk) for 9.9 +/- 4.0 yr (from 6.8 +/- 4.7 to 17.7 +/- 1.3 yr of age) with a mean height gain of 2.6 +/- 1.4 sd score. GH secretion was reevaluated by arginine insulin (n = 15) or propanolol glucagon (n = 3) test after 0.5 +/- 0.6 yr of GH withdrawal. At reevaluation, peak GH was more than 10 mug/liter in four patients (22%; range, 11.7-19.5 microg/liter; group I), between 5 and 10 microg/liter in three patients (17%; range, 7.3-9 mug/liter; group II), and less than 5 microg/liter in 11 patients (61%; range, 0-4.7 microg/liter; group III). A positive correlation was found between serum IGF-I and peak GH levels after attainment of adult height (P = 0.007). Only one of the seven patients who showed increased GH secretion ability in adulthood (groups I and II) demonstrated other hormonal deficiencies (gonadotropin and adrenal insufficiencies). Among the 11 patients with persistent severe GHD (group III), 10 (91%) of the 11 subjects were shown to have multiple pituitary hormone deficits after attainment of adult height. The structure of the hypothalamo-pituitary axis differs among groups [i.e. patients who showed increased GH secretion ability in adulthood (groups I and II) vs. those who remained severely GHD (group III)]. The location of the EPPHS was significantly different among groups (P < 0.003). The EPPHS was found at the median eminence in all but one of group III patients and along the pituitary stalk (proximal stalk) in all but one of group I and II patients. The pituitary stalk was visible and described as normal (n = 1) or thin (n = 6) in all group I and II patients, whereas the pituitary stalk was not visible even after enhancement in seven of the 11 group III patients (P < 0.02). The prevalence of anterior pituitary hypoplasia and the mean height gain sd score were similar in each group. In conclusion, only 61% of patients with childhood-onset GHD and EPPHS remained severely GHD, and thus suitable for GH therapy, in adulthood. Although the pathogenesis of anterior pituitary dysfunction remains unclear in patients with ectopic neurohypophysis, isolated GHD, location of EPPHS along the stalk, and visibility of the pituitary stalk on magnetic resonance imaging findings clearly represent important markers to predict a less severe form of the disease.
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PMID:Do all patients with childhood-onset growth hormone deficiency (GHD) and ectopic neurohypophysis have persistent GHD in adulthood? 1554 1

Given the lack of published guidelines regarding the use of trophic factors to treat patients with short bowel syndrome (SBS), a group of experts in the field convened to discuss best-practice strategies. Trophic factors, such as recombinant human growth hormone (r-hGH) and glucagon-like peptide-2 (GLP-2), may enhance intestinal adaptation and decrease parenteral nutrition (PN) requirements; therefore, their utility in treating SBS patients was evaluated. Available clinical data on use of r-hGH therapy in SBS patients were discussed, as were the utility of r-hGH in the PN weaning process, the optimal timing of r-hGH therapy, and how to select appropriate patients for r-hGH therapy. In addition, contraindications and precautions as well as adverse effects of r-hGH treatment were discussed. The meeting culminated with the development of a treatment algorithm to summarize best-practice recommendations for the management of SBS in adult patients. This algorithm involves attempting to wean patients off PN without the use of trophic factors. If this is unsuccessful, it is recommended that patients be treated with an r-hGH regimen or participate in investigational studies using other trophic factors.
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PMID:Indications and recommendations for the use of recombinant human growth hormone in adult short bowel syndrome patients dependent on parenteral nutrition. 1677 Jan 69


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