Introduction / rôles des reins / circulation rénale / fonction glomérulaire (I) Flashcards
What are the three roles of the kidneys?
- Maintien du milieu intérieur
- Sécretion d’hormones
- Métabolisme
How do the kidneys maintain the “milieu intérieur” ?
control des liquides intra-corporels… leurs volumes/concentrations
How do the kidneys control hormone secretion? (3 “systems”)
- rénine, angiotensine II, prostaglandine, bradukinine —> les vasoactives
- érythropoïtine —> fabrication des GR
- 1,25-dihydroxyvitamine D3 (calcitrol) —> activation du vit. D pour métabolisme du Ca2+/K+
How do the kidneys work on your metabolism?
- catabolisme d’hormones
- gluconéogénèse (2/3 foie, 1/3 reins)
What does the intracellular liquid resemble and why?
Primitive ocean
- Na+ —> 12mM and K+ —> 140mM
- Where life originated therefore the origin of most enzymes and proteins
What is the principal pump that controls the “milieu intérieur”?
Pompe Na-K ATPase
What are the four main components of the urinary system?
What are the two layers of the kidneys?
Interne: médullaire qui termine à la papille
Externe: cortex
What part of the kidneys collects the urine that is formed?
The calice
What irrigates and drains the kidneys?
Irrigue: 1 artère
Draine: 1 veine
Overview of kidney anatomy (macroscopic):
Overview of nephron anatomy:
What are the main components of a nephron?
Glomérule —> filtration
Tubule —> réabsoption et filtration des déchets mal filtrés
- Tubule poximal
- Anse de Henle
- Tubule distal
- Tubule collecteur
What are the three principal functions of nephrons?
- Filtration glomérulaire
- Réabsorption tubulaire
- Sécrétion tubulaire
Where are the different parts of the nephron located?
Glomérule: ALWAYS IN CORTEX
Other aspects are In cortex and medulla…
How much of the débit cardiaque goes to the kidneys?
20%… 1L –> per day
What is the order of vascularization of kidneys?
a. rénale —> a. interlobaires —> a. arquées (arciformes) —> a. interlobulaires (cortex) —> artérioles afférents —> capillaires glomérulaires —> artériole efférente —> capillaires péritubulaires —> système veineux
What are the peritubular capillaries lining the Anse de Henle called?
Vasa recta
When/where does glomerular filtration happen?
Pendant que le sang traverse les capillaires glomérulaires
What collects the blood after it is filtered?
A. efférente —> capillaires péritubulaires (réabsorption/sécrétion tubulaire)
What crosses through the fenestrations in the glomerular capillaries?
Filtrat glomérulaire
Where is the filtrat glomérulaire taken and where is it collected?
Collected in espace de Bowman and taken towards proximal tubule
What is found at the center of a group of the glomerular capillaries?
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
What are the 3 layers of the paroi capillaire?
- Cellule endothéliale fenestrée
- Membrane basale (collagène type IV)
- Podocyte avec pédicelles —> recouvre anses capillaires
- Enserrent les anses capillaires
