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)

Hyperglucagonaemia and hypergastrinaemia were observed in some severely burnt patients during their illness. Hyperglucagonaemia seemed to be related to the severity of illness rather than to the burn itself, and the close correlation of glucagon concentrations with glucose and urea and its inverse correlation with bicarbonate concentrations suggest that glucagon might contribute to the hypercatabolic state. One patient developed high levels of gastrin and massive bleeding from a stress ulcer of the duodenum. Possibly gastrin hypersecretion may have a role in the pathogenesis of Curling's ulcer.
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PMID:Hypersecretion of glucagon and gastrin in severely burnt patients. 112 28

A new technique is described for evisceration in the rat in which liver function is preserved. These animals lack all known sources of glucagon and insulin and are capable of active gluconeogenesis, urea formation and ketone body production by the liver. Measurements of blood levels of the metabolites of the caloric substrates showed that, unlike the classical eviscerate preparation, these animals maintain high blood glucose, urea and ketone body levels for up to 72 hr as contrasted with the profound decrease in these constituents in the absence of the liver. Survival time is also significantly extended from about 6 hr in rats lacking liver function to 72 hr or more when the liver is viable. This new surgical preparation is a valuable tool for studying the role of the liver in absence of the known gastroentero-pancreatic hormones. It would also be utilized as a model of "acute" diabetes.
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PMID:Metabolic studies in eviscerated rats with functional livers. 112 30

Experiments were carried out with the isolated perfused liver of the overnight-starved rat to study the control of the conversion of the essential amino acid threonine to glucose and urea from the point of view of its conservation when in short supply. The relationships between the concentration of added L-threonine and the rate of glucose and urea production showed that both pathways have considerable capacity and were saturated at a high (15 mM) concentration of threonine. However, these concentration-rate relationships were sigmoidal, so that at low concentrations the rates of conversion were disproportionately low. Thus at physiologic levels of threonine, no measurable stimulation of glucose or urea output was observed. Hepatic uptake of threonine was similarly disproportionately reduced at near-physiologic levels. Glucagon stimulated glucose and urea outputs in parallel fashion and stimulated the uptake and inward membrane transport of threonine at both saturating and low concentrations. This and the changes in intracellular and extracellular concentrations of threonine indicate the transport is rate limiting for both pathways. If this is so, the apparent restrictive property probably resides at the plasma membrane. Since the liver is the end point of threonine metabolism, this property would effectively limit the utilization of threonine when in short supply.
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PMID:Restriction of hepatic gluconeogenesis and ureogenesis from threonine when at low concentrations. 121 4

The inner medullary collecting duct (IMCD) of the rat consists of two structurally and functionally distinct segments, i.e., the initial and the terminal IMCD. To identify factors that may regulate the transport function in the IMCD segments, we assessed whether catecholamines, carbachol, prostaglandin E2 (PGE2), bradykinin, glucagon, calcitonin, parathyroid hormone, or epidermal growth factor affects adenosine 3',5'-cyclic monophosphate (cAMP) production in microdissected tubules in the presence and absence of arginine vasopressin (AVP, 0.1 nM). All experiments were performed in the presence of 3-isobutyl-1-methylxanthine, and cAMP was measured by radioimmunoassay. Epinephrine (greater than or equal to 50 nM) and clonidine (greater than or equal to 1 microM) markedly decreased AVP-induced cAMP levels in both IMCD segments. However, phenylephrine did not show an effect. The inhibitory effect of epinephrine was blocked by yohimbine (50 nM) but not by prazosin (50 nM). In isolated perfused terminal IMCDs, epinephrine inhibited AVP-stimulated urea permeability. Isoproterenol (1 microM), in the absence of AVP, caused a significant increase in cAMP level only in the initial IMCD. Propranolol (1 microM) inhibited this isoproterenol effect, but atenolol did not. Dopamine (less than or equal to 1 microM) had no effect on cAMP levels in either IMCD segment. Carbachol, PGE2, and the various peptide hormones had no effect on cAMP levels (+/- AVP) in either IMCD segment. We conclude that an adrenergic beta 2-receptor is present only in the initial IMCD, where its occupation increases cAMP production. We conclude also that an adrenergic alpha 2-receptor is present in both IMCD segments, where its occupation inhibits AVP-induced cAMP production.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hormone and autacoid regulation of cAMP production in rat IMCD subsegments. 135 41

Test meals with 25 g protein in the form of cottage cheese or egg white were given with or without 50 g glucose to male subjects with mild to moderately severe, untreated, type II diabetes. Water was given as a control meal. The glucose, insulin, C-peptide, alpha amino nitrogen (AAN), glucagon, plasma urea nitrogen (PUN), nonesterified fatty acid (NEFA), and triglyceride area responses were determined using the water meal as a baseline. The glucose area responses following ingestion of cottage cheese or egg white were very small compared with those of the glucose meal, and were not significantly different from one another. The serum insulin area response was 3.6-fold greater following ingestion of cottage cheese compared with egg white (309 v 86 pmol/L.h). The simultaneous ingestion of glucose with cottage cheese or egg white protein decreased the glucose area response to glucose by 11% and 20%, respectively. When either protein was ingested with glucose, the insulin area response was greater than the sum of the individual responses, indicating a synergistic effect (glucose alone, 732 pmol/L.h; glucose with cottage cheese, 1,637 pmol/L.h; glucose with egg white, 1,213 pmol/L.h). The C-peptide area response was similar to the insulin area response. The AAN area response was approximately twofold greater following ingestion of cottage cheese compared with egg white. Following ingestion of glucose, it was negative. When protein was ingested with glucose, the AAN area responses were additive. The glucagon area response was similar following ingestion of cottage cheese or egg white protein. Following glucose ingestion, the glucagon area response was negative.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Metabolic response to cottage cheese or egg white protein, with or without glucose, in type II diabetic subjects. 140 1

The efficacy of urea synthesis as measured by functional hepatic nitrogen clearance (i.e., the relation of urea synthesis rate to blood alpha-amino nitrogen concentration) was studied before and after diet protein supplementation in six healthy subjects and five patients with stable cirrhosis (galactose elimination capacity about 60% of control). Daily protein intake was increased for 14 days by a protein-enriched liquid from (mean +/- S.D.) 1.01 +/- 0.32 g/kg body wt. to 1.62 +/- 0.31 g/kg body wt in the control subjects, and from 0.69 +/- 0.21 g/kg body wt. to 1.50 +/- 0.15 g/kg body wt. in the patients with cirrhosis. This increased the hepatic nitrogen clearance from 27 +/- 10 l/h to 39 +/- 15 l/h in the control subjects (p less than 0.05) and from 15 +/- 6 l/h to 21 +/- 7 l/h in the cirrhosis patients (p less than 0.05). There was no effect on the galactose elimination capacity in any group. Compared to the control subjects, the response in hepatic nitrogen clearance relative to the increase in protein intake was reduced by 60% in the patients. Basal glucagon was 75% higher in the patients and increased by 50% during high protein intake (p less than 0.05), but did not parallel the increase in hepatic nitrogen clearance, and it did not change in the control subjects. The study shows that an increase in protein intake selectively increases liver function with regard to disposal of amino nitrogen; the mechanism is qualitatively intact but quantitatively deficient in patients with cirrhosis of the liver, and does not seem to depend on glucagon.
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PMID:Effects of an increase in protein intake on hepatic efficacy for urea synthesis in healthy subjects and in patients with cirrhosis. 150 Jun 87

Twenty-eight Angora goat doelings (average BW 22.1 kg) were used in a 150-d study to examine the effects of dietary CP level and degradability on mohair fiber production. A 2 x 2 factorial arrangement was instituted using conventional, solvent-extracted soybean meal (high degradability) or expelled, heat-treated soybean meal (low degradability) incorporated into low- (12%) or high- (19%) CP diets. Grease and clean mohair weights were greater (P less than .05) in goats fed the diets containing 19% CP. Mohair fiber diameter was not affected (P greater than .10) by dietary CP level. Clean mohair weight tended (P less than .08) to be higher in the goats fed diets containing expelled, heat-treated soybean meal. Body weight gains were not affected (P greater than .10) by CP level or degradability, whereas DMI increased (P less than .01) with increasing CP level. Ruminal fluid pH and total VFA concentrations were not affected (P greater than .10) by diet. Ruminal ammonia N concentration increased (P less than .05) as CP level in the diet increased, and postprandial changes in concentrations were less noticeable in the group fed expelled, heat-treated soybean meal. Plasma urea N (P less than .001) and total protein (P less than .01) concentration increased as dietary CP level increased. Plasma glucose was elevated (P less than .001) 2 h after feeding in the goats fed conventional, solvent-extracted soybean meal, whereas glucagon concentrations were greater at 0 and 4 h in the group fed expelled, heat-treated soybean meal.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Dietary protein level and ruminal degradability for mohair production in Angora goats. 152 21

Eight men with untreated type II diabetes were given 480 mL water containing 15 g, 25 g, 35 g, and 50 g fructose orally, in random sequence. The same subjects were given the same volume of water as a control. They also were given 50 g glucose on two occasions for comparative purposes. Plasma glucose, urea nitrogen, and glucagon, and serum insulin, C-peptide, alpha-amino-nitrogen (AAN), nonesterified fatty acids (NEFA), and triglycerides were determined over the subsequent 5-hour period. The area responses to each dose of fructose were calculated and compared with the water control. The integrated glucose area dose-response was curvilinear, with little increase in glucose until 50 g fructose was ingested. With the 50-g dose, the area response was 25% of the response to 50 g glucose. The insulin response also was curvilinear, but the curve was opposite to that of the glucose curve. Even the smallest dose of fructose resulted in a relatively large increase in insulin, and a near-maximal response occurred with 35 g. The area response to 50 g fructose was 39% of that to 50 g glucose. The C-peptide data were similar to the insulin data. The AAN area response to fructose ingestion was negative. However, the response was progressively less negative with increasing doses. The glucagon area response was positive, but a dose-response relationship was not apparent. The glucagon area response was negative after glucose ingestion, as expected. The urea nitrogen area response was negative, but again, a dose-response relationship to fructose ingestion was not present.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The metabolic response to various doses of fructose in type II diabetic subjects. 158 30

Injection with pharmacological doses of dexamethasone (5 mg/kg) and/or bovine glucagon (1 mg/kg) exerts pronounced effects on toadfish liver compared with vehicle-treated control fish. Affected parameters include hepatic levels of glycogen and the activities of glutamate dehydrogenase, aspartate aminotransferase, malate dehydrogenase, and enzymes involved in NADPH generation as well as the kinetics of pyruvate kinase. Activities of tyrosine aminotransferase, however, a prime target for hormonal induction in mammals, remain unchanged in Opsanus. In subsequently isolated toadfish hepatocytes, metabolite concentrations and flux through gluconeogenesis are altered as are in vitro responses to epinephrine and catfish glucagon in previously injected fish. Contrary to existing mammalian models, short-term regulation of urea cycle activity can be ruled out for toadfish, since hormone treatments fail to influence the activity of two ornithine-urea cycle enzymes or the rate of hepatocyte-urea synthesis. Treatment-dependent increases in hepatic glutamine synthetase, the unique feeder enzyme for ammonia "nitrogen" in fish urea cycle, indicate a potentially pivotal role for this enzyme in longer-term regulation of ureogenesis.
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PMID:Metabolic actions of glucagon and dexamethasone in liver of the ureogenic teleost Opsanus beta. 160 Dec 63

Clearance experiments were performed in anesthetized male Wistar rats to reevaluate the renal effects of glucagon (Gluc) on glomerular filtration rate (GFR) and solute and water excretion. After an 80-min control period, these effects were evaluated in the last 80 min of a 2-h intravenous Gluc infusion. Gluc induced significant increases in GFR (+20%), urine flow rate (+150%), free water reabsorption (+50%), urea synthesis and urea excretion (+66%), and nonurea solute excretion (+67%). In addition, fractional urea excretion (FEurea) increased by 43% (P less than 0.01). Additional experiments showed that increases in either urea excretion or urine flow rate (induced by appropriate infusion of urea or half-dilute saline), similar to those seen after Gluc, could not account for the increased FEurea. All significant effects of Gluc were also observed during infusion of antidiuretic hormone or during water diuresis. The tubular effects of Gluc could be explained by a reduction in proximal reabsorption. The dose of Gluc required to induce all the effects described above was 12 ng.min-1.100 g body wt-1, a dose producing an approximately 10-fold supraphysiological peripheral plasma concentration but a "physiological" level for the liver. Infusion of 1.2 ng induced almost no change in renal function, and infusion of 120 ng induced no greater effects than 12 ng. These results suggest 1) that Gluc, a hormone liberated after protein ingestion, exerts coordinated effects on liver and kidney to increase simultaneously urea synthesis and excretion and to promote water conservation and 2) that these effects could, at least in part, be indirect and depend on the Gluc-induced stimulation of hepatocyte metabolism.
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PMID:Effects of glucagon on glomerular filtration rate and urea and water excretion. 163 42


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