Major Hormone Flashcards Preview

Yr 2 Endocrine > Major Hormone > Flashcards

Flashcards in Major Hormone Deck (30):
1

Includes

Thyroid hormone
Insulin
Glucagon
Epinephrine
Cortisol
Aldosterone
Somatostatin
Parathyroid hormone
Calcitriol
Growth Hormone

2

What stimulates & inhibits Thyroxine release?

S] Cold Pregnancy & Exercise

I] Glucocorticoids e.g. cortisol & Somatostatin

3

What does thyroxine do?

Increases:
- Metabolic rate
- Thermogenesis
- Lipolysis
- Gluconeogenesis
- Proteolysis
- GH receptor expression (permissive)

Involved in foetal brain development

4

What triggers & inhibits insulin release?

S]
- Blood Glucose
- Blood Amino acids
- Vagal Activity
- Glucagon
- Incretin hormones

I]
- Somatostatin
- Sympathetic (alpha2 receptors)
- Stress e.g. hypoxia

5

What does insulin do?

Increases:
- Glucose uptake
- Glycogen synthesis
- Amino acid uptake
- Protein synthesis
- TAG synthesis
- K+ Entry to cells

Permissive to GH

Inhibits gluconeogenesis


Antagonizes Cortisol

6

What is Glucagon?

A peptide hormone produced by Alpha cells in pancreas.

Serves to raise blood glucose

7

What stimulates/inhibits Glucagon?

S]
- Low blood glucose
- High blood amino acids
- Sympathetic Activity via epinephrine
- Cortisol
- Stressfull stimuli e.g. exercise or infection

I]
- Insulin
- High blood glucose
- Somatostatin
- Free FA/Ketones

8

What does glucagon do?

- Promotes Gluconeogenesis
- Lipolysis
- Glycogenolysis

9

What is epinephrine?

A catecholamine produced in adrenal medulla

Serves the fight/flight instinct

10

What stimulates/inhibits epinephrine?

Sympatetic activity

11

Functions of epinephrine?

- Peripheral vasodilation
- Lipolysis
- Gluconeogenesis
- Glycogenolysis

12

What is cortisol?

A steroid hormone (glucocorticoid) produced in the zona fasciculata of the adrenal cortex.

13

What alters cortisol produciton?

CRH --> ACTH

14

What does cortisol do?

Immunity:
- Suppresses Immunity

Calcium:
- Inihibits Osteoblasts
- Increases renal Ca2+ excretion
- Decreases Gut Ca2+ Absorption

Thyroid:
- Inhibits TSH release

Glucose:
- Permissive to GLucagon
- Decreases insulin sensitivity
- Proteolysis/Lipolysis/Gluconeogenesis

Water:
- In high concs it functions like aldosterone

Stimulates Somatostatin

Permissive to norepinephrine (vasoconstriction)

15

How can diabetes cause osteoporosis?

Cortisol inhibits osteoblasts and lowers serum Ca2+
-> More PTH
-> Bone resorption
-> Osteoporosis

Normally insulin antagonizes cortisol, diabetics just get osteoporosis

16

What is aldosterone?

A steroid hormone (mineralocorticoid) produced in the zona glomerulosa of the adrenal cortex

17

What stimulates/inhibits aldosterone?

S]
Low blood volume, low BP or hyperosmolar blood through the RAAS

I] opposite

18

What does aldosterone do?

Increases Na+ reabsorption and K+ excretion at kidney tubule to raise blood volume

19

What is somatostatin?

AKA GHIH
Trophic peptide hormone produced by the hypothalamus and Delta cells of the pancreas

20

What stimulates/inhibits somatostatin release?

S]
Cortisol
REM sleep
Free FAs
High glucose

21

What does somatostatin do?

Inhibits GH release
Slows nutrient absorption
Inhibits Glucagon/insulin release

22

What is parathyroid hormone?

A peptide hormone released by the parathyroid glands

23

What stimualtes PTH?

Low serum Ca

24

What does PTH do?

Raises serum calcium by:
- Stimulating calcitriol release from kidney/liver
- inhibits osteoblasts/stimulates osteoclasts
- Increases renal phosphate excretion
- Increases renal Ca2+ reabsorption

25

What is calcitriol?

aka Active Vit D3 or 1,25-dihydroxycholecalciferol

Steroid hormone released from kidney and liver

26

What stimulates/inhibits calcitriol?

S]
- PTH
- Prolactin

27

What does calcitriol do?

Raises serum Ca2+ by:
- Increases Ca2+ absorption from gut
- Increases renal Ca2+ reabsorption
- Stimulates osteoclasts

28

What is growth hormone?

A trophic peptide hormone releases from the Ant. Pituitary

29

What stimulates/inhibits Growth Hormone?

S]
- Insufficient energy e.g. hypoglycaemia or exercise/cold
- High Plasma AAs
- Stressfull stimuli (stress.infection)
- Delta sleep
- Sex steroids

I]
- Rem Sleep
- Cortisol
- FAs
- Glucose

30

What does GH do?

- Cartilage formation in long bones through IGF-1
- Gluconeogenesis
- Decreases insulin sensitivity
- Sensitizes adipocytes to epinephrine (permissive effect)
- Increases AA uptake & protein synthesis