Recap of normal endocrine function

Question 1

Characteristics of Amino-based Hormones?

Answer 1

1. Water soluble
2. Travel in blood freely
3. Bind to cell surface receptor

Question 2

Ex. of PROTEIN & PEPTIDE HORMONES?

Answer 2

Insulin, glucagon, GLP-1

Question 3

Ex. of AMINES & AMINO ACIDS hormones?

Answer 3

Adrenaline (and thyroxine*) … derived from tyrosine

Question 4

Characteristics of Steriod Hormones & ex?

Answer 4

1. Lipid soluble
2. Travel in blood bound to carrier
3. Bind to intracellular receptor
4. *Thyroid hormones (but derived from amines)
5. e.g. cortisol, oestrogen, testosterone, aldosterone

Question 5

Endocrine glands are stimulated to synthesize and release hormones in response to one of three stimuli.

Answer 5

1. Hormonal stimuli
2. Neural stimuli
3. Humoral stimuli
   The production of many hormones is regulated by negative feedback

Question 6

What is humoral stimuli?

Answer 6

Hormones stimulate other endocrine organs to release their hormones:

Question 7

Hypothalamic hormones stimulate the release of most_____hormones?

Answer 7

Anterior Pituitary

Question 8

Anterior pituitary hormones stimulate targets to release?

Answer 8

more hormones

Question 9

Hormones from the final target organs inhibit the release?

Answer 9

of AP and Hypothalamic hormones

Question 10

Hypothalamic is what type of hormone?

Answer 10

Releasing hormone

Question 11

AP releases what types of hormones?

Answer 11

Tropic hormone

Question 12

What is neural stimuli?

Answer 12

Nerve fibers stimulate hormone release from glands such as the medulla

Question 13

What is humoral stimuli?

Answer 13

Changing blood levels of ions and nutrients directly stimulate secretion of hormones

Question 14

Ex. of humoral stimuli?

Answer 14

1. Declining blood Ca2+ concentration stimulates parathyroid glands to secrete PTH (parathyroid hormone)
2. PTH causes Ca2+ concentrations to rise, and stimulus is removed

Question 15

Target gland hormone from target gland inhibit the release of?

Answer 15

Releasing & tropic hormones

Question 16

Adrenal cortex hormones?

Answer 16

1. Mineralocorticoids (Aldosterone) – stimulated by high K+ in blood and angiotensin II to increase Na+ and water in blood
2. Glucocorticoids (Cortisol) – stimulated by ACTH during stress for protein, lipid and glucose metabolism, and supress immune system for resistance against stress
3. Androgens –

Question 17

Adrenal medulla hormones?

Answer 17

Epinephrine & norepinephrine stimulated by sympathetic nerves for sympathetic functions during stress

Question 18

Low levels of T3 & T4 hormones, metabolic rate or puberty, or pregnancy stimulate the secretion of?

Answer 18

Thyrotropin-releasing-hormone TRH in the hypothalamus

Question 19

How is short-term stress regulated?

Answer 19

1. APs triggered by the hypothalamus travel to the adrenal medulla
2. Medulla secretes 80% epinephrine and 20% norepinephrine
3. epinephrine & norepinephrine reinforce other sympathetic responses to make ready for “fight or flight”
4. High BP, increased HR, and respiration, metabolic rate

Question 20

How is long-term stress regulated?

Answer 20

1. Stressor cause hypothalamic neurons to release CRH
2. CRH travel to AP
3. AP release ACTH
4. ACTH travels to adrenal cortex
5. Adrenal cortex releases glucocorticoids (cortisol) and some mineralocorticoids
6. Glucocortocoids have metabolic effects and increase breakdown of fat, protein and glycogen for energy and suppress immune system
7. Mineralocorticoids work on renals and retain salt and water = high BP