Synonym

N/A

Tubes

• Lavender top tube, chilled
• 5 mL venous blood

Additional information

• Handle sample gently to prevent hemolysis
• Send it to lab immediately on ice slurry

Info

• This test measures the blood concentration of the hormone, glucagon
• Glucagon is a peptide hormone originating from the alpha cells of the islets of Langerhans in the pancreas
• This hormone acts primarily on the liver:
• Stimulates glucose production stored in the form of glycogen (glycogenolysis)
• Stimulates the synthesis of additional glucose on depletion of glucose stores (gluconeogenesis)
• Glucagon also has a minor effect of enhancing lipolysis of triglycerides in adipose tissue
• Glucagon stimulates urea production

Clinical

• The clinical utility of glucagon levels include:
• Aids in the diagnosis of hypoglycemia due to chronic pancreatitis or idiopathic glucagon deficiency
• Aids in the diagnosis of suspected glucagonoma, an alpha islet-cell neoplastic tumor
• Evaluation of suspected renal failure or renal transplant rejection
• Glucagon secretion is stimulated by:
• Hypoglycemia
• Increased catecholamines such as epinephrine and norepinephrine
• Increased plasma amino acids
• Sympathetic nervous system
• Acetylcholine
• Cholecystokinin
• Glucagon secretion is inhibited by:
• Hyperglycemia
• Insulin
• Somatostatin
• Glucagonoma (familial) may be manifested by 3 different syndromes:
• The first syndrome exhibits
• Anemia
• Diabetes mellitus or impaired glucose tolerance (IGT)
• Glucagon levels >1000 pg/mL or >1000 ng/L
• Necrolytic migratory erythema (characteristic skin rash)
• Venous thrombosis
• Weight loss
• The second syndrome - severe diabetes mellitus
• The third Syndrome - Multiple Endocrine Neoplasia (MEN) Type 1

Additional information

• Glucagon is released in episodic spikes, with variation within a day being ~33%
• Radioactive/Nuclear medicine scans/tests performed within 48 hrs or lipemic samples interfere with glucagon test results
• Abnormally high glucagon levels drop toward normal once insulin therapy effectively controls diabetes
• Related laboratory tests include:
• Glucagon suppression test
• Glucose (blood/serum)
• Glucose tolerance tests
• Glycated hemoglobin A1C
• Insulin
• Microalbumin

Nl Result

Consult your laboratory for their normal ranges as these may vary somewhat from the ones listed below.

High Result

Conditions associated with elevated glucagon levels include:

• Acromegaly
• Cushing's syndrome
• Diabetes mellitus (type 2)
• Exercise
• Fasting
• Glucagonoma (pancreatic alpha cell tumor)
• Hepatic cirrhosis
• Hyperlipidemia
• Hyperosmolality
• Hypoglycemia
• Kidney transplant rejection
• Obesity
• Pancreatitis (Acute)
• Pheochromocytoma
• Protein rich meal
• Renal failure (Chronic)
• Stress due to
• Burns
• Surgery
• Trauma
• Uremia
• Drugs
• Arginine (amino acids)
• Cholecystokinin
• Danazol
• Epinephrine
• Gastrin
• Glucocorticoids
• Insulin
• Nifedipine

Low Result

Conditions associated with decreased glucagons levels include:

• Chronic pancreatitis
• Cystic fibrosis
• Idiopathic glucagon deficiency
• Immediately after meal, especially if high in carbohydrates
• Loss of pancreatic tissue
• Pancreatectomy
• Pancreatic neoplasms
• Drugs
• Atenolol
• Pindolol
• Propranolol
• Secretin
• Verapamil

References

• Al-Haddad M et al. Glucagon for the Relief of Esophageal Food Impaction Does It Really Work? Dig Dis Sci. 2006 Sep 27; [Epub ahead of print].
• ARUP Laboratories®. Glucagon. [Homepage on the internet]©2007. Last accessed on September 27, 2007. Available at URL: http://www.aruplab.com/guides/ug/tests/0099165.jsp
• eMedicine from WebMD®. Glucagonoma Syndrome. [Homepage on the Internet] ©1996-2006. Last updated on December 5, 2006. Last accessed on September 27, 2007. Available at URL: http://www.emedicine.com/derm/topic168.htm
• Fanelli CG et al. Glucagon: the effects of its excess and deficiency on insulin action. Nutr Metab Cardiovasc Dis. 2006 Mar;16 Suppl 1:S28-34. Epub 2006 Feb 9.
• Kang TW et al. [Clinical features of neuroendocrine tumor of the pancreas: single center study] [Article in Korean]. Korean J Gastroenterol. 2006 Aug;48(2):112-8.
• Laboratory Corporation of America®. Glucagon, Plasma. [Homepage on the internet]©2003. Last updated on July 31, 2007. Last accessed on September 27, 2007. Available at URL: http://www.labcorp.com/datasets/labcorp/html/chapter/mono/sr002200.htm
• MedlinePlus Medical Encyclopedia®. Glucagon.[Homepage on the Internet]©2005. Last updated on September 6, 2007. Last accessed on September 27, 2007. Available at URL: http://www.nlm.nih.gov/medlineplus/ency/article/003716.htm
• Moran TH. Gut peptide signaling in the controls of food intake. Obesity (Silver Spring). 2006 Aug;14 Suppl 5:250S-3S.
• Nauck MA et al. Effects of glucagon-like peptide 1 on counterregulatory hormone responses, cognitive functions, and insulin secretion during hyperinsulinemic, stepped hypoglycemic clamp experiments in healthy volunteers. J Clin Endocrinol Metab. 2002 Mar;87(3):1239-46.
• Nuttall FQ et al. Effect of orally administered phenylalanine with and without glucose on insulin, glucagon and glucose concentrations. Horm Metab Res. 2006 Aug;38(8):518-23.