SCT III - Gastrointestinal Tract: Secretion Flashcards
What is the dominant acini in the sublingual gland?
100% Mucus
What is the dominant acini in the submandibular gland?
75% Serous
25% Mucus
What is the dominant acini in the parotid gland?
100% Serous
What innervates the salivary glands?
Facial N. (CN VII)
Glossopharyngeal N. (CN IX)
What is the composition of serous saliva?
Amylase
Immune Function
- Lysosyme
- IgA ABs
- Calcium binding proteins
What is the composition of mucus saliva?
Mucin
What is the function of saliva?
- Lubrication
- Bactericidal effects
- Digestion
Chloride secretion in acinar cells (drawing)
How do ducts modify saliva?
Na+ & Cl- Reabsorption
K+ & HCO3- Secretion
What happens to the viscosity of the saliva at slow secretion rates?
Viscosity ↑
What happens to the viscosity of the saliva at rapid secretion rates?
Viscosity ↓
What is the sympathetic regulation of salivary secretion?
SNS
- Small amount
- Thick & viscous
- Via β-2 Receptors
- Blocked by -lol (Propanolol) causing dry mouth
What is the parasympathetic regulation of salivary secretion?
PNS
- Large amount
- Thin & viscous
- Via mAChR
- Blocked by atropin causing dry mouth
Which enzyme catalyzes the reaction between water and carbon dioxide to later aid in the formation of HCl?
Carbonic anhydrase
What type of transport protein is the K+/H+ pump?
Primary active transporter
What are the stimulants of HCl production?
- ACh
- Gastrn
- Histamine
- GRP/Bombasin (via PNS)
What are the inhibitors of HCl production?
- Somatostatin
- Prostaglandins
What causes stress ulcers?
Sympathetic regulation of G-cells to release Gastrin, releasing HCl for no reason (no food)
What are the phases of gastric juice production?
Cephalic 20-30%
Gastric 60-70%
What are the stimulants of pancreatic juice secretion?
- ACh (mAChR) via Vagus N. (CN X)
- CCK (CCK(A))
- Secretin
- VIP via VD (more blood flow stimulates)
What are the inhibitors of pancreatic juice secretion?
Somatostatin
What are the phases of pancreatic juice production?
Cephalic 20%
Gastric 5-10%
Intestinal 70%
What are the choleretic effects of bile emptying?
Choleretic = control amount
- Secretin
- VIP
What are the cholekinetic effects of bile emptying?
Cholekinetic = control rate
- CCK
- ACh (PNS)
- Fats
- MgSO4
What transport is used to empty bile contents into bile cuniculi in the liver?
ABC Transporters