Salivary and Gastric Secretions

What are the COMPONENTS of Saliva?

What are SALIVARY ENZYMES?

Major Salivary Glands - PAROTID

Parotid salivary gland

1) Inferior and anterior to the ears

2) Watery secretions

3) Majority of salivary amylase production (~ 25% of total

Major Salivary Glands - SUBMANDIBULAR

Submandibular salivary gland

1) Floor of the mouth, medial to the mandible

2) Mixed serous and mucus secretions

Major Salivary Glands - SUNBLINGUAL

Sublingual salivary gland

1) Below the tongue, superior to the submandibular

2) Most viscous secretions, mostly for lubrication

Structure of the Salivary Gland

What are the FUNCTIONAL UNITS of Salivary Glands?

Functional unit of the salivary glands

1) Clusters of acinar cells around a central cavity from the acinus

2) Ductal cells form the connecting ducts

3) Contractile myoepithelial cells aid secretion

Formation of Hypotonic Saliva - ACINAR FORMATION

1) Cl^- is actively pumped through acinar cells into the acinus

2) Na⁺ flows through leaky tight junctions

3) H₂O follows from the cells and the leaky tight junction

4) Salivary solution is now isotonic

Formation of Hypotonic Saliva - DUCTAL MODIFICATION

1) Tight junctions in ductal cells are not leaky so water can’t pass out

2) Cl^- and Na⁺ ions are removed from saliva

3) K⁺ and HCO₃^- (bicarbonate) are secreted into the saliva

4) This then makes the saliva hypotonic as it passes through the ducts

Salivary Flow Rate & Composition

Question 1

Autonomic Regulation of Salivary Secretions

Parasympathetic Innervation

Sympathetic Innervation

What is SJOGREN’S SYNDROME?

Question 2

What are the MAJOR FUNCTIONS of the Stomach?

Stomach Wall Physiology

What are the CONTENTS of Gastric Juice?

How is HCL produced?

Question 3

Regulation of Gastric Acid Secretions

Gastrin Physiology

Phases of Gatric Secretion

Gastric Mucosal Resistance

What is ACUTE GASTRITIS?

What is AUTOIMMUNE GASTRITIS?

Question 4