Digestive System 2.1: Bile Flashcards
8 Roles of Acetylcholine
Stimule production de salive aqueuse
Stimule motricité oesophagienne et relaxation sphincters oesophagiens
Stimule relaxation réceptive fundus gastrique (effectuée par NO/VIP)
Stimule péristaltisme gastrique
Stimule sécrétion HCl (cellules pariétales)
Stimule sécrétion pancréatique (relâche CCK)
Stimule contraction vésicule biliaire
Stimule péristaltisme intestinal et colique
Ihibition of gastrine release
pH < 3.5
Role of Gastrin (2)
stimulation sécrétion HCl (Cellules pariétales), a
ctive motricité estomac
Cholécystokinine (CCK) roles (2)
Inhibition vidange gastrique (frein duodénal)
Sécrétion enzymes pancréatiques
Motiline role
Stimule contractions gastriques interdigestives
Somatostatine Role:
Principale hormone inhibitrice (régulatrice) du système GI
What is the main role of Bile?
Important for the breakdown of lipids
participent à formation micelles → which can then be broken down by lipases
What is special about sels biliares?
Sels biliares and bilirubin need to be conjugated
Conjugation = more soluble
IF some of them are sent to bile without being conjugated they will be reabsorbed back to the liver to be conjugated
NEVER non conjugated
Sels biliaires primaires
Properties and what they are
Forme par foi à partir de cholesterol
Cholate
Chenodeoxycholate
What do bacteria in the intestinal tract do?
form acides biliares secondaires
de-conjugate molecules
What is cycle entero-hepatique:
Sels biliaires participent à digestion lipides
Ensuite réabsorbés dans iléon et recyclés au foie
95% of the sels biliaires will be reabsorbed in the iléon
What kind of diet would lead to high acides biliares?
A diet that is rich in lipids
What are the transporters for acides biliares from blood to liver and what kind of acids are these?
**Transporters: **
NTCP and OATP
Type: Conjugated
Transporteir qui permet la sécrétion de sels biliaires conjugués dans canalicule biliaire
BSEP
What is the role of ASBT?
Réabsorption sels biliaires dans iléon
What is the role of the biliary vesicle?
Stores bile when not needed and concentrates it for use when a rich in lipid food is injested
What is the danger with bile vesicle concentrating bile?
he stored bile will be concentrated
This is done via the reabsorption of water
There is a danger of perticipating the constituents!!
Because of water loss, the concentration becomes less soluble
precisely: if we have a lot of cholesterol and not a lot of bilirubin or water to keep it soluble → formation of rocks
