Search Results
Search for other papers by Julia K Panzer in
Google Scholar
PubMed
Search for other papers by Alejandro Caicedo in
Google Scholar
PubMed
innovations reveal unexpected biology. There is no doubt that several important techniques paved the way for the modern era of glucagon research. The late Roger Unger understood that developing the glucagon radioimmunoassay was crucial to determine the
Department of Poultry Science, University of Arkansas, Fayetteville, Arkansas, USA
Search for other papers by Bishnu Adhikari in
Google Scholar
PubMed
Institute of Basic Medical Sciences, Faculty of Medicine, The Norwegian Transgenic Centre (NTS), University of Oslo, Oslo, Norway
Faculty of Biosciences and Aquaculture (FBA), Nord University, Steinkjer, Norway
Search for other papers by Prabhat Khanal in
Google Scholar
PubMed
Search for other papers by Mette Olaf Nielsen in
Google Scholar
PubMed
Introduction Glucagon plays a key role in glucose homeostasis due to its stimulating effect on hepatic glucose output in response to low blood glucose levels ( Jiang & Zhang 2003 ). In addition, glucagon has also been suggested to be a
Department of Genomic Drug Discovery Science, Graduate School of Pharmaceutical Sciences, Kyoto University Faculty of Pharmaceutical Sciences, Kyoto University, Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
Search for other papers by Yoko Fujiwara in
Google Scholar
PubMed
Department of Genomic Drug Discovery Science, Graduate School of Pharmaceutical Sciences, Kyoto University Faculty of Pharmaceutical Sciences, Kyoto University, Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
Search for other papers by Masami Hiroyama in
Google Scholar
PubMed
Department of Genomic Drug Discovery Science, Graduate School of Pharmaceutical Sciences, Kyoto University Faculty of Pharmaceutical Sciences, Kyoto University, Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
Search for other papers by Atsushi Sanbe in
Google Scholar
PubMed
Department of Genomic Drug Discovery Science, Graduate School of Pharmaceutical Sciences, Kyoto University Faculty of Pharmaceutical Sciences, Kyoto University, Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
Search for other papers by Junji Yamauchi in
Google Scholar
PubMed
Department of Genomic Drug Discovery Science, Graduate School of Pharmaceutical Sciences, Kyoto University Faculty of Pharmaceutical Sciences, Kyoto University, Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
Search for other papers by Gozoh Tsujimoto in
Google Scholar
PubMed
Department of Genomic Drug Discovery Science, Graduate School of Pharmaceutical Sciences, Kyoto University Faculty of Pharmaceutical Sciences, Kyoto University, Yoshida Shimoadachi-cho, Sakyo-ku, Kyoto 606-8501, Japan
Search for other papers by Akito Tanoue in
Google Scholar
PubMed
during lactation ( Moos et al. 1989 , Young et al. 1996 ). In addition to these physiological roles, AVP and OT are known to regulate the circulating blood glucose level by stimulating insulin and glucagon release ( Dunning et al. 1984 , Gao et
Search for other papers by Ivan Quesada in
Google Scholar
PubMed
Search for other papers by Eva Tudurí in
Google Scholar
PubMed
Search for other papers by Cristina Ripoll in
Google Scholar
PubMed
Search for other papers by Ángel Nadal in
Google Scholar
PubMed
Introduction The principal level of control on glycaemia by the islet of Langerhans depends largely on the coordinated secretion of glucagon and insulin by α- and β-cells respectively. Both cell types respond oppositely to changes in blood glucose
Search for other papers by Linda Ahlkvist in
Google Scholar
PubMed
Search for other papers by Bilal Omar in
Google Scholar
PubMed
Search for other papers by Anders Valeur in
Google Scholar
PubMed
Search for other papers by Keld Fosgerau in
Google Scholar
PubMed
Search for other papers by Bo Ahrén in
Google Scholar
PubMed
Introduction Islet dysfunction in type 2 diabetes is bi-hormonal involving both defective insulin secretion and augmented glucagon secretion ( Unger & Orci 1975 ), the latter resulting in chronic elevation of circulating glucagon levels ( Larsson
Search for other papers by D. PAULINE ALEXANDER in
Google Scholar
PubMed
Search for other papers by R. ASSAN in
Google Scholar
PubMed
Search for other papers by H. G. BRITTON in
Google Scholar
PubMed
Search for other papers by D. A. NIXON in
Google Scholar
PubMed
Whilst it is well known that the foetal pancreas of several species contains insulin there is little information available concerning the presence of glucagon in foetal life. In the work reported in this paper the concentration of glucagon or 'glucagon-like' material was estimated in the maternal and foetal plasma, pancreas, parts of the gastro-intestinal tract and amniotic and allantoic fluids of the sheep.
Pregnant ewes bearing foetuses aged 59–143 days (term 148 days) were anaesthetized by the spinal administration of procaine hydrochloride. The foetus was exposed by Caesarian section during which samples of the amniotic and allantoic fluids were removed. Catheters were inserted into a maternal dorsalis pedis artery and a tributary of an umbilical artery. Heparinized blood samples were removed simultaneously from the mother and foetus within 15 min of inducing spinal anaesthesia. The plasma was separated immediately by centrifugation at 4 °C. Tissue samples from the pancreas and
Search for other papers by Li Wang in
Google Scholar
PubMed
The Second Affiliated Hospital of Medical School, Center of Experiment Teaching, School of Biomedical Sciences, Xi'an Jiao Tong University, Xi'an 710004, People's Republic of China
Search for other papers by Yufeng Zhao in
Google Scholar
PubMed
Search for other papers by Baosong Gui in
Google Scholar
PubMed
Search for other papers by Rongguo Fu in
Google Scholar
PubMed
Search for other papers by Feng Ma in
Google Scholar
PubMed
Search for other papers by Jun Yu in
Google Scholar
PubMed
Search for other papers by Ping Qu in
Google Scholar
PubMed
Search for other papers by Lei Dong in
Google Scholar
PubMed
Search for other papers by Chen Chen in
Google Scholar
PubMed
insulin resistance, causing an increase in blood glucose level ( Weir & Bonner-Weir 2004 , Prentki & Nolan 2006 , Wajchenberg 2007 ). The islet α-cell also regulates blood glucose level by secreting glucagon, which activates gluconeogenesis to increase
Search for other papers by L van Bloemendaal in
Google Scholar
PubMed
Search for other papers by J S ten Kulve in
Google Scholar
PubMed
Search for other papers by S E la Fleur in
Google Scholar
PubMed
Search for other papers by R G Ijzerman in
Google Scholar
PubMed
Search for other papers by M Diamant in
Google Scholar
PubMed
), oxyntomodulin (OXM) and glucagon-like peptide 1 (GLP-1), have been identified as players in the regulation of feeding by relaying meal-related information on nutritional status to the brain. Based on more than three decades of experimental evidence from rodent
Search for other papers by T. P. Mommsen in
Google Scholar
PubMed
Search for other papers by T. W. Moon in
Google Scholar
PubMed
ABSTRACT
Salmon glucagon-like peptide (GLP), bovine glucagon (B-glucagon) and anglerfish glucagon (AF-glucagon), all activate glucose production in teleost hepatocytes through gluconeogenesis and glycogenolysis, but notable species differences exist in their respective effectiveness. In trout hepatocytes, gluconeogenesis appears to be the main target of hormone action. In eel cells, sampled in November, glycogenolysis was activated threefold, while gluconeogenesis was increased by 12% only. In March, glycogenolytic activation was 1·7-fold, while gluconeogenesis was increased by about 1·7-fold after exposure to B-glucagon. In brown bullhead cells, increases in glycogenolysis from seven- (GLP) to tenfold (B- and AF-glucagon) were noted, while activation of gluconeogenesis was slight. Fragments of two AF-glucagons (19–29) revealed only insignificant metabolic activity. Treatment of eel cells with B-glucagon led to large (up to 20-fold) increases in intracellular cyclic AMP (cAMP) concentrations, while exposure to GLP was accompanied by a modest (< twofold) increase in cAMP, although metabolic effectiveness (gluconeogenesis and glycogenolysis) was similar for the two treatments. Under identical conditions, brown bullhead cellular cAMP responded poorly. Levels of cAMP peaked within 15 min following hormone application. The results imply that no simple or direct relationship exists between the amount of intracellular cAMP and the metabolic action of the glucagon family of hormones. It can further be concluded that GLPs are important regulators of hepatic metabolism, influencing identical targets as glucagon, while the mechanisms of action seem to differ.
Journal of Endocrinology (1990) 126, 109–118
Search for other papers by F Bertuzzi in
Google Scholar
PubMed
Search for other papers by C Berra in
Google Scholar
PubMed
Search for other papers by C Socci in
Google Scholar
PubMed
Search for other papers by A M Davalli in
Google Scholar
PubMed
Search for other papers by G Pozza in
Google Scholar
PubMed
Search for other papers by A E Pontiroli in
Google Scholar
PubMed
Abstract
Hyperglucagonemia is commonly found in insulin-dependent as well as in non-insulin-dependent diabetes mellitus, and is likely to be caused by absolute or relative insulin deficiency. The aim of the present study was to evaluate whether a chronic glucagon exposure (1·0 μm for 4 h) modifies the insulin response to acute stimuli with glucagon (1·0 μm), arginine (10·0 mm) and glucose (16·7 mm), or the glucagon response to arginine and glucose, in human islets. Chronic exposure to glucagon did not affect the insulin response to glucose and arginine, but inhibited its response to glucagon (44·6 ± 9·3 vs 168·6 ± 52·3 pg/islet per 20 min, P<0·05); the latter effect was not observed when exposure to glucagon was discontinuous (2·0 μm glucagon alternated with control medium for 30 min periods). The chronic exposure to glucagon also reduced the glucagon response to arginine (−4·9 ± 5·7 vs 19·9 ± 7·9 pg/islet per 20 min, P<0·05) without affecting the inhibition of glucagon release exerted by glucose. These data indicate that chronic exposure to glucagon desensitizes pancreatic α and β cells in response to selected stimuli.
Journal of Endocrinology (1997) 152, 239–243
