Osmoregulation

Question 1

Control of osmoregulation involves 2 main processes
- Involves what tasks (4)

Answer 1

3

Question 2

Cellular dehydration
- Osmolarity, direction of fluid

Osomolarity changes when extracellular volume decreases

Answer 2

4

Question 3

Renin-angiotensin-aldosterone circuit
- Know enzymes/prohormones/hormones
- How aldosterone impacts kidney + brain regions/behav

Answer 3

5
15

Question 4

Aldosterone interacts w/ which part adrenal cortex?

Answer 4

Cortex (shell)
- Medulla (inner part) only interacts w/ catecholamines

11

Question 5

Functions of aldosterone (5)

Answer 5

12

Question 6

How and where is thirst and drinking behav stimulated?
- Where are these organs located?

Where are osmoreceptors located? (Stimulation of vasopressin release and increase aquaporins in kidney)

Answer 6

Plasma angiotensin II -> Vasopressin stimulated from pars nervosa (neurohypophysis)
- Via stim of supraoptic nucleus (SON) and paraventricular nucleus (PVN)
16

SON: Anterior to (in front of) PVN
PVN: Within hypothalamus, dorsal to (above) pituitary gland
21
—
Organum vasculosum of the lateral terminalis (OVLT); circumventricular organ
Anteroventral tip of the 3rd ventricle (AT3V)

Question 7

(bradykinen and angiotensin II antagonism)
Kininogen and prorenin
- Vasodilation or vasoconstriction?

Answer 7

18

Question 8

Cardiovascular regulation of renin-angiotensin-aldosterone circuit

Answer 8

20

Question 9

If vasopressin (AVP) is released for prolonged time in response to prolonged stressor, what is released?

Vasopressin receptors found where? (V1, V2) Interplays with what?

Answer 9

ACTH from adenohyphysis
30

Heart, liver, kidney
Myocyte hypertrophy (leads to cardiovascular heart failure w/ longterm stressor)
31

Question 10

Atrial natriuretic peptide (ANP)
- What it does, where it’s located
- Impact on kidney (3), adrenal cortex (1), brain (2)

Answer 10

32
33

Question 11

Osmoregulation in fish:
- Freshwater vs Saltwater vs Cartilaginous fish
- Urophysis (what is is and what interacts w/ it)
- Fresh water fish neurointermediate lobe secretion vs Seawater fish urophysis secretion

Answer 11

Hyperosmotic: H2O excretion, NaCl retention
Hypoosmotic: H2O retention, NaCl excretion
39

Urotensin, cortex, medulla, dahlgren cells, spinal cord
42

Vasotocin
Urotensin-II
45