Hormones: Their regulation of blood glucose
What are the two most important hormones for regulating blood glucose?
1. Insulin 2. Glucagon
What is the main hormone release in response to hypoglycemia? Where is it released from?
-Glucagon -The alpha cells of the Islets of Langerhans in the pancreas
When is insulin secreted and from where?
When blood glucose levels increase it is secreted from the beta cells of the pancrea's Islets of Langerhans
What are the two ways glucagon raises blood glucose?
1. Hepatic glycogenolysis (breakdown of glycogen to glucose in the liver) 2. Gluconeogenesis (Creation of glucose from non-carbohydrates)
What are the five ways insulin lowers blood glucose?
1. Diffusion of glucose into cells 2. Active transport of amino acids into cells 3. Glycogenesis 4. Protein synthesis in cells 5. Lipogenesis (triglyceride synthesis)
What produces GH? What hormones govern it's release and where do they come from?
-the anterior pituitary -GHRH and GHIH from the hypothalamus
Low blood glucose stimulates the release of GHRH or GHIH? High blood glucose stimulates the release of GHRH or GHIH?
GH contributes to glucose metabolism by (3): It's overall effect of GH is to ______ blood glucose
-Increase 1. Helping to stimulate glycogenolysis 2. Stimulating lipolysis 3. Metabolic effects like stimulating protein synthesis
Where is cortisol produced? What stimulates it's production?
-The adrenal cortex -ACTH (Adrenocorticotropic hormone)
What are cortisols three main functions regarding glucose regulation? It's over all effect is to _____ blood glucose
-Increase 1. Promotes protein catabolism 2. Promotes lipolysis 3. Promotes gluconeogenesis
Where is thyroxine produced? How does it contribute to glucose regulation (2)? It's overall effect is to ________ blood glucose
-Thyroid 1. Increases glycolysis 2. Increases lipolysis -maintain
What are the two catecholamines?
Epinephrine and Norepinephrine
Where are the catecholamines produced? What are the two ways affect blood glucose? It's overall effect is to _______ blood glucose
-Adrenal Medulla 1. Promotes glycogenolysis 2. Promotes lipolysis -increases
During hormonal regulation in the absorptive (fed) state insulin is involved in decreasing glucose in it's 5 ways, what two other hormones work during this state and in what way?
-Thyroxine and GH are involved in protein synthesis during the absorptive (fed) state
In the post absorptive (_____) state what two hormones are involved in glycogenolysis? Where does this occur?
-fasting -Glucagon and epinephrine -muscle fibers and hepatocytes
In the post absorptive (fasting) state what five hormones are involved in promoting lipolysis? Where does this occur?
1. Epinephrine 2. Norepinephrine 3. Cortisol 4. GH 5. Thyroxine -Adipose cells
In the post absorptive (fasting) state what hormone is involved in promoting protein breakdown? Where does this occur?
-Cortisol -Most body cells (especially skeletal muscles)
In the post absorptive (fasting) state what two hormones are involved in promoting gluconeogenesis? Where does this occur?
1. Glucagon 2. Cortisol -Hepatocytes (and kidney cortex cells during starvation)
During a period of hyperglycemia protein _______ is promoted by the hormones ______, ______ and ____ _______ to help lower blood glucose
-synthesis -insulin, thyroxine and growth hormone
During a period of hypoglycemia protein _______ is promoted by the hormone ______ to help raise blood glucose
-catabolism (breakdown) -cortisol