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What is glucagon?

2 years ago

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O

Orie Lockman


80 Answers

A
Aisha

Glucagon is a hormone secreted (released) by the pancreas.

The páncreas is made up of different types of cells like alpha cells and beta cells.

Glucagon is released specifically from alpha cells.

What does it do?

It just increases the glucose (a type of sugar) levels in your blood - this is important because it means the glucose levels in your blood never get too low.


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 It is a peptide hormone, produced by alpha cells of the pancreas. It works with other hormones such as insulin to control glucose levels in the blood.

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Zoe-Leigh Sly

Glucagon is a hormone that stimulates and regulates blood sugar in the liver, breaks down glycogen (sugar) to release into the blood as glucose, it also breaks down amino acids and triglycerides (fat) into glucose for fuel for the body.

S
Srishti

Glucagon is a hormone produced by the alpha cells of the pancreas. It breaks down glycogen stores to raise the concentration of glucose.

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Thanks for your question Orie.


Glucagon is a hormone that is involved in controlling blood sugar (glucose) levels. It is produced by the alpha cells, found in the islets of Langerhans, in the pancreas, from where it is released into the bloodstream.


Glucagon works in tandem with insulin in order to regulate (maintain homeostatic balance). Insulin helps to move glucose out of the blood stream, say after a meal containing carbohydrates, and into cells throughout the body. Glucagon can then be used during period of fasting (not eating for a period of 4hours or more) in order to break down stored glucose and move it back into the blood stream. We want to try and maintain our circulating blood glucose concentrations at around 4.5 to 5.5 mmol/L throughout the day.

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Glucagon is a hormone, secreted into the blood by alpha cells in the Islets of Langerhans, small groups of cells situated in the pancreas. Glucagon works with insulin in a negative feedback loop that responds to low and high levels of glucose in the blood (see diagram below)


Glucagon is secreted, by the alpha cells when blood glucose levels are LOW, this is HYPOGLCAEMIA. Glucagon activates the enzyme GLYCOGEN PHOSPHORYLASE, primarily in the liver, this breaks down the carbohydrate glycogen (complex sugar) into glucose (simple sugar) in a process called GLYCOGENOLYSIS. The glucose is released into the blood. More glucose is released by the breakdown of amino acids and lipids in the liver.


The effect is to increase blood glucose concentration and maintain HOMEOSTASIS.




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Hi Orie


Glucagon is a hormone formed in the pancreas. It is released in response to low blood glucose levels which may occur after periods of exercise.

Glucagon has three main functions:

  • Stimulates the liver to break down glycogen into glucose, which is then released into the blood.
  • The breakdown of triglycerides into fatty acids.
  • The process of gluconeogenesis, this is the conversion of amino acids into glucose.


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Farzana Begum

Glucagon is a hormone that is involved in controlling blood sugar (glucose) levels. It is produced by the alpha cells, found in the islets of Langerhans, in the pancreas, from where it is released into the bloodstream.


So what is the action of glucagon? The pancreas detects low blood glucose concentration and this may happen if you haven't eaten for a while. Alpha cells in the pancreas secrete glucagon. Glucagon (1st messenger) travels in the bloodstream and binds with complimentary glycoprotein receptors on liver cells to form a hormone receptor complex (HRC). HRC causes a membrane bound enzyme to change in tertiary structure and the active site consequently becomes complementary to ATP. ATP is then converted to cAMP (2nd messenger) (Adenylate cyclase catalyses the cyclization of ATP to cAMP. cAMP activates protein enzyme kinase which converts glycogen to glucose. Glucose moves out of the cell by facilitated diffusion and the blood glucose concentration goes back to normal. This is an example of negative feedback.

P
Pakiza Seerat

Glucagon is hormone formed in the pancreas which promotes the breakdown of glycogen to glucose in the liver.



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Glucagon is a hormone in the body which causes stored glycogen to be converted into glucose. When blood sugar levels are low the pancreas releases glucagon into the bloodstream. This causes glycogen stores in the liver and muscles to break down into glucose (glycogen is simply a long chain of glucose molecules joined together). This release of glucose into the blood restores the blood sugar level back to normal.

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Bestun Ramadhan

A hormone that converts stored glycogen to glucose

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Glucagon is a hormone secreted by alpha cells in the pancreas into the blood. It travels through the blood and connects to specialized receptors on liver cells and delivers to them the following message : The level of glucose in the blood is low, I need you to convert glycogen (stored glucose) into glucose and release it into the blood. It is only secreted when specialized cells in the pancreas sense that the blood glucose levels are low. Think of it as the opposite of insulin. Insulin is secreted when the blood glucose is high and glucagon is secreted when blood glucose is low. We usually give synthetic glucagon as a medicine during hypoglycemia (very low blood sugar) usually when patients with type 1 diabetes take a higher dose of insulin than required. It immediately elevates the patient’s blood sugar and reverses the actions of insulin. Hope that helped.

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Hi Orie,

Glucagon is a pancreatic hormone, produced by alpha cells of the pancreas. It raises concentration of glucose and fatty acids in the bloodstream.


If the concentration of glucose in the blood decreases below a certain level, cells may not have enough glucose for respiration and may not be able to function properly. The control of blood glucose level is a key part of homeostasis. Blood glucose concentration is controlled by two hormones secreted by endocrine tissue in the pancreas. This tissue is made up of a group of cells known as the islets of Langerhans.


I hope this helps.



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A
Aleena

Glucagon is a hormone released by alpha cells in the islets of langerhan in the pancreas when blood glucose levels are low. It acts as a secondary messengers model along with adrenaline in order to stimulate glycogenolysis, gluconeogenisis and decrease rates of respiration in order to increase blood glucose levels

C
Caitlin Ames-Hopkins

Glucagon is a hormone that stimulates the breakdown of glycogen into glucose, increasing the blood-glucose concentration. It is produced in the Isle of Langerhans of the pancreas.

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