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)

His-DTrp-Ala-Trp-DPhe-LysNH2, [His1,Lys6] GHRP, is a new synthetic hexapeptide which specifically elicits a dosage-related release of GH in vitro and in vivo without a concomitant release of LH, FSH, TSH, or PRL and, in limited in vivo studies, insulin or glucagon. Our results indicate that this small peptide has the attributes of a hypophysiotropic hormone. In vitro the minimum and maximum active dosages ranged from 1-10 ng/ml in the pituitary incubate assay. It was active in rats, monkeys, lambs, calves, and under special experimental conditions chicks, indicating its lack of species dependency. It was active when administered iv, sc, or ip to rats. After iv injection, GH levels rose within 2 min, peaked at +10-20 min, and by 2 h usually had returned to normal. It was not possible to directly compare the potencies of [His1,Lys6]GHRP, and the GH-releasing factors GHRF-44 and GHRF-40 after a single sc injection in rats because the time course of the GH response of these peptides was different. The GH response of [His1,Lys6]GHRP was longer in duration than either of these larger peptides. Both SRIF-14 and SRIF-28 inhibited the GH response of the hexapeptide; however, SRIF-28 was about four times more active than SRIF-14 in vitro and 7.5 times more active in vivo. When this small peptide was administered sc once or twice daily to immature rats for 9 or 25 days, the BW gain increased above the control. At the end of the weight gain studies the pituitary remained fully responsive to the peptide. Thus, [His1,Lys6] GHRP may be a valuable peptide for investigating the function of the pituitary somatotrophs and, in addition, it has the potential for increasing BW gain of a variety of normal animals by inducing GH release via a direct pituitary site of action.
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PMID:On the in vitro and in vivo activity of a new synthetic hexapeptide that acts on the pituitary to specifically release growth hormone. 671 55

A dose-dependent increase in body length and weight can be induced in Snell dwarf mice by human, porcine and bovine growth hormones, ovine prolactin, bovine TSH, T4 and T3, and to a lesser extent by insulin. In contrast, porcine FSH, equine LH, testosterone, oestradiol and glucagon influenced neither body length nor weight. Beside body length and weight, the weight of many organs is stimulated by hormonal treatment. GH, T4 and T3 have a rather similar spectrum of effects, with exceptions for the skinfold and epididymal fat-pads. LH had no effect, but in contrast FSH had a strong effect on the seminal vesicles and a less pronounced one on the testis. Oestradiol induced a marked enlargement of the uterus, whereas testosterone increased the weights of the kidneys and seminal vesicles. The main action of insulin is probably localized on body fat. Glucagon, however, did not stimulate organ growth. These data illustrate again the complexity of hormonal regulation of growth.
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PMID:The effects of pituitary, thyroid, pancreatic and sexual hormones on body length and weight and organ weights of Snell dwarf mice. 672 29

Perifusion of rat thyroid fragments was performed to study short-term effects of TSH, theophylline and glucagon on thyroid hormone secretion. This technique proved to be relatively convenient and sensitive, and gave reproducible results for at least 3 h, permitting precise kinetic studies of response to hormonal and pharmacological agents without any interference. There was a significant (P less than 0.001) linear correlation between the log TSH concentrations over the range 20-150 mu./ml and thyroid response. A second stimulation, using the same concentration of TSH, did not differ from the first stimulation if they were separated by an active 'washing' period of only 15 min. Theophylline also had a stimulating effect and like TSH induced an early release of the hormone fraction with a peak between 2 and 4 min, but it did not potentiate the TSH effect. Perifusion of rat thyroid fragments was found to be a useful tool for analysing dynamic effects of various substances. These effects were significant for periods of time as short as 20 min. Each thyroid preparation could be used a second time for another pharmacological or hormonal test. Our preliminary results also suggested that there was a direct glucagon effect on thyroid hormone secretion with a dose-response correlation.
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PMID:Use of the perifusion technique on rat thyroid fragments in the study of thyroid hormone secretion: short-term effects of thyrotrophin, theophylline and glucagon. 673 52

We have assessed the effect of omeprazole (30 mg daily) on gastric acid secretion as well as on basal hormone levels (fasting gastrin; TSH, T3, T4, TBG; insulin, glucagon, C-peptide; prolactin, testosterone, 17-beta-oestradiol, dihydroepiandrosterone, cortisol and PTH) in 8 healthy volunteers before and after a 28 day treatment. On day 29, i. e. one day after the last omeprazole dose, mean stimulated acid output was still reduced from 27.4 +/- 3.5 mmol H+/h (+/- SEM) to 7.8 +/- 1.4 mmol H+/h (72% inhibition). Fasting gastrin levels were raised from 55.5 +/- 6.8 pg/ml to 80.9 +/- 6.7 pg/ml (33% increase). On day 39, stimulated gastric acid secretion and fasting gastrin levels have been returned to pretreatment values. Basal levels of prolactin, testosterone, TSH, T3, T4, TBG, cortisol, PTH, 17-beta-oestradiol, insulin, glucagon, c-peptide, dihydroepiandrosterone remained unchanged by a 28-day omeprazole treatment. Omeprazole is a highly effective antisecretory compound without any effect on the basal hormone levels tested. Even after 28 days its effect on acid secretion and fasting gastrin levels was fully reversible.
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PMID:[4 weeks' administration of omeprazole: effect on acid behavior and basal hormone levels]. 674 Dec

Inhibition studies of nuclear binding of labelled insulin by unlabelled insulin, proinsulin and polypeptide hormones (glucagon, GH, TSH) as well as kinetics of binding dissociation suggest that thyroid isolated nuclei specifically, at least pro parte, and reversibly bind to insulin.
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PMID:[Specificity and reversibility of insulin binding to isolated thyroid nuclei]. 677 Oct 40

Spontaneous diabetes mellitus has been characterized in a line of nonobese purebred keeshond dogs as an insulin-requiring hereditary disorder with onset at between 2 and 6 mo of age. Diabetic dogs developed cataracts, became ketotic, hyperglycemic, hypercholesterolemic, lipemic, and hypoinsulinemic. Basal glucagon, cortisol, and T4 serum concentrations and responses to ACTH, TSH, and arginine were normal. Light microscopic studies of the pancreas by immunocytochemical procedures revealed the absence of islet B cells, the presence of A cells, and solitary B cells. Diabetic dogs had poor fecundity, and a single puberal diabetic male had poor semen quality and was unable to sire pups. Parents of diabetics and nondiabetic siblings were normal. This spontaneous form of diabetes mellitus, with similar lesions to the insulin-dependent diabetes of people, will be a valuable aid to comparative biomedical research of diabetes mellitus.
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PMID:Inherited, early onset, insulin-requiring diabetes mellitus of Keeshond dogs. 699 41

The relationship between non-esterified fatty acid (NEFA) mobilization and hepatic conversion to plasma triglycerides (TG), as modulated by diazoxide-induced effects upon endogenous catecholamine, glucagon, and insulin secretion, was examined in vivo in the rat. Thyrotropin (TSH)-induced NEFA mobilization provided the control study.--In all control experiments, TSH (1.5 IU/100 g) induced a 110% increase in NEFA availability, which was associated with a subsequent 52% increase in plasma TG concentration and a 73% increase in plasma ketone bodies. Following diazoxide administration (30 mg/kg), endogenous secretion of both catecholamines and glucagon was observed, resulting in a comparable 100% increase in NEFA availability, with the appropriate ketonaemic response. However, in contrast to the control TSH study, plasma triglyceride concentration did not increase. This suppression was secondary, at least in part, to a direct 40% inhibition of hepatic secretion of triglycerides.--Although plasma NEFA concentration is an important determinant of plasma triglyceride levels, the concurrent concentration of endogenous catecholamines, glucagon, and insulin modulate the hepatic conversion of NEFA to triglycerides in vivo.
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PMID:The effect of diazoxide-induced hormonal secretion on plasma triglyceride concentration in the rat. 699 2

Synthetic neurotensin was infused into five healthy subjects at a mean dose of 2.3 pmol/kg . min for 30 min, producing a rise in plasma neurotensin concentrations, measured by RIA of 104 +/- 10 (mean +/- SEM) pmol/liter. The mean disappearance half-time on stopping the infusion was 3.8 +/- 0.2 min. The MCR was 16 +/- 1 ml/kg . min, and the apparent space of distribution was 88 +/- 6 ml/kg. During the neurotensin infusions, plasma pancreatic polypeptide rose by 145 +/- 54 pmol/liter. In contrast to results in experimental animals, there was no significant change in the pulse or blood pressure of the subjects or any significant change in blood glucose or plasma concentrations of insulin, glucagon, gastric inhibitory peptide, gastrin, motilin, or vasoactive intestinal peptide. Similarly, there was no change in plasma concentrations of TSH, GH, PRL, LH, and FSH.
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PMID:Neurotensin infusion in man: pharmacokinetics and effect on gastrointestinal and pituitary hormones. 700 47

The removal of extracellular, endogenously produced adenosine in isolated rat adipocytes by treatment with adenosine deaminase enhanced their responsiveness to various lipolytic agents, i.e. the response to catecholamines, glucagon, LH, TSH, and cholera toxin was elicited at concentrations that were 10-500 times lower than those required for the stimulation of lipolysis in untreated cells in vitro. The removal of adenosine from intact fat cells largely potentiated the isoproterenol-stimulated increase in cAmP level. However, a similar treatment of undissociated segments of adipose tissue failed to influence further the response to isoproterenol. These results strongly suggest that in the intact adipose tissue, adenosine and related nucleosides are absent and do not function as modulators of adenylate cyclase or lipolysis. Under these circumstances the estimated "low" physiological concentrations of the neurotransmitters in the adipose tissue are able to modulate lipid mobilization. Previous studies have shown that insulin failed to inhibit lipolysis, induced by micromolar norepinephrine concentrations, in adenosine-free adipocytes. The present study demonstrates that at physiological catecholamine concentrations, insulin is a potent antilipolytic agent.
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PMID:Evaluation of adenosine or related nucleosides as physiological regulators of lipolysis in adipose tissue. 704 12

Bombesin, a peptide with widespread biological actions, has been demonstrated in human tissues by immunological methods. To investigate its effect in man, synthetic bombesin was infused at low doses in six male volunteers. Bombesin at 2.4 pmol kg-1 min-1 produced significant rises in plasma insulin, glucagon, pancreatic polypeptide, gastrin, cholecystokinin, motilin, glucose-dependent insulinotropic polypeptide, neurotensin, enteroglucagon, vasoactive intestinal polypeptide, and serum calcium. In contrast, bombesin caused a profound fall in parathyroid hormone levels and reduced plasma glucose concentrations. A late rise in plasma calcitonin was also observed. Bombesin had no significant effect on the pituitary hormones, TSH, GH, PRL, or cortisol. No hormonal changes or alterations in calcium were noted during saline infusions. Bombesin has a marked stimulatory effect on gastrointestinal hormones, which is unique and opposite to the effect of somatostatin, a potent inhibitor of gut hormone release. Bombesin also influences calcium-regulating hormones, either directly or through its action on gut hormones. The bombesin concentrations achieved with the dosages used were low enough to indicate a possible physiological role for the endogenous peptide.
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PMID:Bombesin: action on gut hormones and calcium in man. 706 3


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