Introduction / rôles des reins / circulation rénale / fonction glomérulaire (I)

Question 1

What are the three roles of the kidneys?

Answer 1

1. Maintien du milieu intérieur
2. Sécretion d’hormones
3. Métabolisme

Question 2

How do the kidneys maintain the “milieu intérieur” ?

Answer 2

control des liquides intra-corporels… leurs volumes/concentrations

Question 3

How do the kidneys control hormone secretion? (3 “systems”)

Answer 3

1. rénine, angiotensine II, prostaglandine, bradukinine —> les vasoactives
2. érythropoïtine —> fabrication des GR
3. 1,25-dihydroxyvitamine D3 (calcitrol) —> activation du vit. D pour métabolisme du Ca2+/K+

Question 4

How do the kidneys work on your metabolism?

Answer 4

1. catabolisme d’hormones
2. gluconéogénèse (2/3 foie, 1/3 reins)

Question 5

What does the intracellular liquid resemble and why?

Answer 5

Primitive ocean

1. Na+ —> 12mM and K+ —> 140mM
2. Where life originated therefore the origin of most enzymes and proteins

Question 6

What is the principal pump that controls the “milieu intérieur”?

Answer 6

Pompe Na-K ATPase

Question 7

What are the four main components of the urinary system?

Answer 7

Question 8

What are the two layers of the kidneys?

Answer 8

Interne: médullaire qui termine à la papille

Externe: cortex

Question 9

What part of the kidneys collects the urine that is formed?

Answer 9

The calice

Question 10

What irrigates and drains the kidneys?

Answer 10

Irrigue: 1 artère

Draine: 1 veine

Question 11

Overview of kidney anatomy (macroscopic):

Answer 11

Question 12

Overview of nephron anatomy:

Answer 12

Question 13

What are the main components of a nephron?

Answer 13

Glomérule —> filtration

Tubule —> réabsoption et filtration des déchets mal filtrés

1. Tubule poximal
2. Anse de Henle
3. Tubule distal
4. Tubule collecteur

Question 14

What are the three principal functions of nephrons?

Answer 14

1. Filtration glomérulaire
2. Réabsorption tubulaire
3. Sécrétion tubulaire

Question 15

Where are the different parts of the nephron located?

Answer 15

Glomérule: ALWAYS IN CORTEX

Other aspects are In cortex and medulla…

Question 16

How much of the débit cardiaque goes to the kidneys?

Answer 16

20%… 1L –> per day

Question 17

What is the order of vascularization of kidneys?

Answer 17

a. rénale —> a. interlobaires —> a. arquées (arciformes) —> a. interlobulaires (cortex) —> artérioles afférents —> capillaires glomérulaires —> artériole efférente —> capillaires péritubulaires —> système veineux

Question 18

What are the peritubular capillaries lining the Anse de Henle called?

Answer 18

Vasa recta

Question 19

When/where does glomerular filtration happen?

Answer 19

Pendant que le sang traverse les capillaires glomérulaires

Question 20

What collects the blood after it is filtered?

Answer 20

A. efférente —> capillaires péritubulaires (réabsorption/sécrétion tubulaire)

Question 21

What crosses through the fenestrations in the glomerular capillaries?

Answer 21

Filtrat glomérulaire

Question 22

Where is the filtrat glomérulaire taken and where is it collected?

Answer 22

Collected in espace de Bowman and taken towards proximal tubule

Question 23

What is found at the center of a group of the glomerular capillaries?

Answer 23

Mésangium —> fonction de nettoyage

• Retrouve substance mésangiale et des cellules

Plupart des cellules sont des cellules contractiles qui:

• Peuvent controller la surface deployée de l’anse capillaire

Cellules mésangiales phagocytaires:

• Ménage de certains déchets

Question 24

What are the 3 layers of the paroi capillaire?

Answer 24

1. Cellule endothéliale fenestrée
2. Membrane basale (collagène type IV)
3. Podocyte avec pédicelles —> recouvre anses capillaires
   
   • Enserrent les anses capillaires

Question 25

What is able to cross the paroi capillaire?

Answer 25

Laisse passer librement les petits solutés et empêchent le passage de plus grosses

Question 26

What controls what is able to cross?

Answer 26

Contrôlé par: (barrière mécanique et électrique)

• Taille des pores
• Charge électrique
• Intrinsic electronegativity of basal membrane —> favours passage des cations (+) et repousse les anions (-)