hormones involved in blood glucose

Question 1

What hormone lowers blood glucose by promoting cellular uptake of glucose?

Answer 1

insulin
secreted by pancreatic B cells

Question 2

What hormone raises blood glucose by stimulating glycogen breakdown in the liver?

Answer 2

glucagon
secreted by pancreatic a cells

Question 3

What hormone helps raise blood glucose by promoting gluconeogenesis and reducing glucose uptake by cells?

Answer 3

cortisol

Question 4

What hormone, released in response to food intake, helps lower blood glucose by increasing insulin sensitivity?

Answer 4

Incretins (GLP-1 and GIP)

Question 5

What are the physiological actions of insulin in the body?

Answer 5

Insulin promotes glucose uptake by cells, especially in muscle and adipose tissue, lowering blood glucose levels. It stimulates glycogenesis in the liver and muscles, enhances fat storage by promoting lipogenesis, and inhibits gluconeogenesis and glycogenolysis. I

Question 6

How does glucagon affect the body?

Answer 6

Glucagon increases blood glucose by stimulating glycogenolysis (breakdown of glycogen to glucose) and gluconeogenesis (glucose production from non-carbohydrate sources) in the liver. It also promotes lipolysis in adipose tissue, releasing fatty acids for energy, especially during fasting or low glucose conditions.

Question 7

What is cortisol’s role in glucose regulation and energy metabolism?

Answer 7

Cortisol increases blood glucose levels by promoting gluconeogenesis and reducing glucose uptake in peripheral tissues. It also enhances protein catabolism (breakdown) to provide amino acids for glucose production and promotes lipolysis to increase free fatty acids. These actions help ensure energy availability during prolonged stress or fasting

Question 8

What are the effects of incretins (GLP-1 and GIP) on glucose regulation?

Answer 8

incretins (GLP-1 and GIP) enhance insulin secretion from the pancreas in response to food intake, thereby lowering blood glucose. GLP-1 also slows gastric emptying and suppresses glucagon release, preventing sharp rises in blood glucose post-meal and improving overall insulin sensitivity

Question 9

What is the molecular mechanism of insulin action, and what are its effects on the liver and adipose tissue?

Answer 9

Insulin binds to the insulin receptor, activating a signaling cascade via the PI3K-AKT pathway.
In the liver, this stimulates glycogen synthesis (glycogenesis) and inhibits gluconeogenesis.
In adipose tissue, insulin promotes glucose uptake by increasing GLUT4 transporter expression on the cell surface and enhances lipogenesis by activating lipoprotein lipase (LPL) and inhibiting hormone-sensitive lipase (HSL), leading to fat storage.

Question 10

How does glucagon work at the molecular level, and what are its effects on the liver and adipose tissue?

Answer 10

Glucagon binds to the glucagon receptor, a G protein-coupled receptor,
in the liver, activating adenylate cyclase and increasing cAMP levels. This activates protein kinase A (PKA), stimulating glycogenolysis and gluconeogenesis.
In adipose tissue, glucagon indirectly stimulates lipolysis by activating HSL, releasing free fatty acids for energy, although glucagon’s primary target is the liver.