Salivary and Gastric Secretions

What are the Contents of Saliva?

What are Salivary Enzymes?

Major Salivary Glands- Parotid Salivary Gland

Parotid salivary gland

-Inferior and anterior to the ears

-Watery secretions

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

Major Salivary Glands- Submandibular Salivary Gland

Submandibular salivary gland

-Floor of the mouth, medial to the mandible

-Mixed serous and mucus secretions

Major Salivary Glands- Sublingual Salivary Gland

Sublingual salivary gland

-Below the tongue, superior to the submandibular

-Most viscous secretions, mostly for lubrication

The Structure of Salivary Glands

What is the Functional Unit of Salivary Glands?

1. Functional unit of the salivary glands

2. Clusters of acinar cells around a central cavity from the acinus

3. Ductal cells form the connecting ducts

4. Contractile myoepithelial cells aid secretion

Formation of Hypotonic Saliva- Acinar Formation

Acinar Formation

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

• Na⁺ flows through leaky tight junctions

-H₂O follows from the cells and the leaky tight junction

• Salivary solution is now isotonic

Formation of Hypotonic Saliva- Ductal Modification

Ductal Modification

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

• Cl^- and Na⁺ ions are removed from saliva

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

-This then makes the saliva hypotonic as it passes through the ducts

Salivary Flow Rate & Composition

Which cells in the salivary gland are responsible for secretion of chloride ions in saliva?

Acinar Cells

Autonomic Regulation of Salivary Secretions

Parasympathetic Innervation

Sympathetic Innervation

What is Sjogren’s Syndrome?

Which ganglion does the glossopharyngeal nerve pass through before innervating the parotid gland?

Otic

What are the Major Functions of the Stomach?

Stomach Wall Physiology

What are the Contents of Gastric Juice?

How is HCL Produced?

Which cells in the stomach are responsible for the secretion of histamine?

ECL Cells

Regulation of Gastric Acid Secretion

Gastrin Physiology

Phases of Gastric Secretion

Gastric Mucosal Resistance

What is Acute Gastritis?

What is Autoimmune Gastritis?

Cimetidine acts at which transmembrane site to prevent HCl secretion?

Histamine Receptor H2