OBJECTIVE Given the interest in glucagon antagonism as a potential treatment of diabetes, we tested the hypothesis that glucagon, in concert with insulin, supports the postabsorptive plasma glucose concentration in humans. RESEARCH DESIGN AND METHODS Following preliminary studies that indicated that a peripheral intravenous insulin dose of 0.1 mU x kg(-1) x min(-1) (lower than those used prev...

The ontogenesis of the hepatic glucagon-sensitive adenylate cyclase system has been studied in the rat. With a partially purified liver membrane preparation, fetal adenylate cyclase was less responsive to glucagon than the enzyme from neonatal or adult livers. Similar results were obtained in gently prepared liver homogenates, suggesting that destruction of essential components of the fetal liv...

To examine the significance of brown adipose tissue for the thermogenic response to glucagon, we injected glucagon intraperitoneally into rats (that have glucagon-sensitive brown fat cells) and into hamsters (that have glucagon-insensitive brown fat cells). Although a thermogenic response to glucagon injection was apparently observed in rats, this response was not augmented by cold acclimation ...

PURPOSE It has been found in the chicken that the amount of retinal glucagon mRNA increases during treatment with positive lenses. Pharmacological studies support the idea that glucagon may act as a stop signal for visually induced eye growth. To gain more insight into the functional role of glucagon, the changes of glucagon and glucagon receptor mRNA concentrations in retina and choroid over t...

The pancreatic hormone glucagon hyperpolarizes the liver cell membrane under various conditions. Here we investigated the physiological relevance of this effect by testing the influence of infusions of glucagon antiserum on the liver cell membrane potential in vivo. Intracellular microelectrode recordings of liver cells (up to 60/rat over 2 h) were done in anesthetized male rats. Livers were fi...

INTRODUCTION This case report demonstrates that the differential immunohistochemical reactivities of Siemens' Double Antibody Glucagon compared to DakoCytomation's Polyclonal Rabbit Anti-Human Glucagon allow for pathologic distinction of enteral versus pancreatic glucagonoma. CASE PRESENTATION A 64-year-old Caucasian man was diagnosed with a duodenal enteroglucagonoma following presentation w...

OBJECTIVE Glucagon receptor antagonists and humanized glucagon antibodies are currently studied as promising therapies for obesity and type II diabetes. Among its variety of actions, glucagon reduces food intake, but the molecular mechanisms mediating this effect as well as glucagon resistance are totally unknown. METHODS Glucagon and adenoviral vectors were administered in specific hypothala...

We estimated the influence of acute glucagon applications on (3)H-histamine uptake by the isolated guinea-pig heart, during a single (3)H-histamine passage through the coronary circulation, before and during anaphylaxis, and the influence of glucagon on level of histamine, NO, O2 (-), and H2O2 in the venous effluent during anaphylaxis. Before anaphylaxis, glucagon pretreatment does not change (...

The prevalent view is that the postabsorptive plasma glucose concentration is maintained within the physiological range by the interplay of the glucose-lowering action of insulin and the glucose-raising action of glucagon. It is supported by a body of evidence derived from studies of suppression of glucagon (and insulin, among other effects) with somatostatin in animals and humans, immunoneutra...

Glucagon use in artificial pancreas for type 1 diabetes (T1D) is being explored for prevention and rescue from hypoglycemia. However, the relationship between glucagon stimulation of endogenous glucose production (EGP) viz., hepatic glucagon sensitivity, and prevailing glucose concentrations has not been examined. To test the hypothesis that glucagon sensitivity is increased at hypoglycemia vs....