Endocrine Control Of Fuel Delivery To Cells

Question 1

Why do we need food

Answer 1

Provide fuel to supply energy for work to perform biochemical reactions

To supply basic building blocks

Question 2

How long will the total circulation concentration of glucose, fatty acids and tags in normal individual provide for energy requirements

Answer 2

1-2 hours

Question 3

How long will an average individuals supply of glycogen stored in the liver and muscle ener for

Answer 3

8 hours

Question 4

Why does the body proceed to break down other substances instead of glucose in starvation

Answer 4

To ensure the brain and heart maintain energy supply

Question 5

When are these stores affected

Answer 5

Growth 
After feeding 
Between meals 
Starvation 
Disease
Pregnancy

Question 6

What endocrine structurs are imp for metabolic regulations

Answer 6

Pancreatic endocrine structures 
Anterior pituitary gland 
Liver
Andrenal cortex 
Adrenal medulla 
Thyroid gland

Question 7

What are islets of langehans

Answer 7

The endocrine sec part of the pancreas
Acinar cells
1-2% of pancreatic cells
3 types of sec cells

Question 8

What are the 3 secretory cells of the islets of langehans

Answer 8

Alpha cells - glucagon
Beta cells - insulin
Alpha cells - somatostatin

Question 9

What does insulin favour

Answer 9

Anabolism 
Stimulate conversion - 
Glucose to glycogen 
FFA to tags 
AAS to proteins

Question 10

Is insulin a fed or hungry state hormone

Answer 10

Fed state when a lot of nutrients circulating

Question 11

What does glucagon favour

Answer 11

Stimulating conversion of glycogen to glucose etc

Hungry state

Question 12

What is insulin synthesised as and how is it converted to

Answer 12

Synthesised as pro hormone which is protealytic ally clipped to release mature peptide in secretion granules

Question 13

What are he short lives of insuli and glucagon

Answer 13

Short
Insulin - 30 mins
Glucagon - 10 mins

Question 14

What dos insulin stimulate

Answer 14

Glucose uptake by muscle and adipose tissue leading to reduction blood glucose levels

Causes GLUT4 transporters to be inserted in plasma mem from intracellular stores

Question 15

What are the effects of insulin

Answer 15

Insulin activates the enzymes in liver and muscle which converts glucose to glycogen

In muscle and fat it stimulates the incorporation of amino acids into protein

Stimulates uptake of glucose from blood

Suppresses lipolysis while promote lipogenesis

Anabolic home one

Question 16

What factors promote insulin secretion

Answer 16

Increase circulatory levels of plasma concentration of Glucose

Increase amino acids arginine and leu

Increase parasymp innervation

Increase glucagon

Increase of cck, gastric

Question 17

What are the inhibiting factors of secretion of insulin

Answer 17

Decrease glucose
Increase symp activity
Increase somatostatin release
Increase cortisol

Question 18

Does oral or intravenous infusion glucose induce a hater secretion of insulin

Answer 18

Oral

Question 19

What are incretin hormones

Answer 19

Released form intestine
Glucose like peptide - 1
Glucose dept insulinotropic peptide

Question 20

What do the incretin hormones do

Answer 20

Sec by intestine and stimulate insulin secretion of pancreatic cells
Feed forward mechanism
Regulate appetite

Only potentiate insulin release when plamsa glucose raised

Question 21

Explain type 1 diabetes mellitus

Answer 21

Childhood onset
Little/no insulin

Affects 10-20% diabetics 
Defect beta cells function 
Ketosis develops 
Insulin injections 
Symptoms rapid development

Question 22

Explain type 2 diabetes mellitus

Answer 22

Adult onset common children now too 
Insulin secretion may be normal 
Affect 80-90% 
Defect in insulin sensitivity 
Ketones rare 
Diet and exercise and oral drugs for treatment 
Symptoms slow development

Question 23

How is lack of insulin or impaired cellular repsonse to insulin tested

Answer 23

Oral glucose tolerance test

Question 24

What are the effects of severe diabetes

Answer 24

Very high plasma concentration of glucose after a meal
Glyosuria
Increased lipolysis to break fa for energy instead of glucose
Metab fa and generate a lot of acetyl coA gives ketone bodies and ketosis
Lower blood ph metab acidosis

Question 25

What are the effects of glucagon

Answer 25

Increases hepatic glycogenolysis blood glucose rises
Decrease hepatic glycogen syn
Increases hepatic glycogenolysis
Decreases amino acid uptake in muscle increase as uptake by liver

Catabolic

Question 26

What so the control of glucagon release

Answer 26

Decrease blood glucose increase glucagon secretion

Amino acids like arginine increase glucagon if protein high stim release of insulin and glucagon

If there is a decrease of fatty acid circulation there is an increase of glucagon secretion

Sympathetic nerve activity stimulates release during exercise

Question 27

What are the effects of exercise

Answer 27

Increased sympathetic stimulation

Increases glucagon and decreases insulin

Increases adrenaline

Net effect to increase glucose and fuel output and suppress storage

Question 28

What is metabolism

Answer 28

Refers to all the chemical reactions that occur in the body

Anabolism and catabolism and transformation of proteins carbs and fat