Exocrine Glands

Intralobular vs Interlobular ducts

Intralobular are found within the lobule of the exocrine gland including intercalated ducts and striated ducts. Interlobular are found in the connective septa that separate lobules and receive the intralobuluar ducts and drain the lobes of the gland (main duct).

Do endocrine glands have ducts?

No, so release into connective tissue

What do sebaceous glands secrete?

On the skin they secrete a waxy, oily substance called sebum- acne.

2 Primary Types of Glands

Endocrine and Exocrine

1. What do mixed glands contain? 2. Give 2 examples

1. Both serous and mucous secretory units 2. Submandibular and sublingual glands

Pancreas 1. Classification of gland according to shape. 2. Since it is so simlar to the parotid gland, how do you distinguish?

1. Compound acinar 2. Islets of Langerhans, centroacinar cells and absence of striated ducts.

Parotid Gland 1. Classification shape 2. Type of secretion 3. Describe the intralobular ducts

1. Compound acinar 2. Purley serous 3. intercallated and striated

Submandibular gland 1. Classification according to shape 2. Type of secretion 3. Describe the intralobular ducts

1. Compound tubuloacinar 2. Mixed with primarily serous. Serous by themselves and as demilunes (half moon shaped on the edge of mucous cells) 3. Intercalated discs are short and striated ducts are prominent

Sublingual Gland 1. Classification according to shape 2. Secretion 3. Describe the intralobular ducts

1. Compound tubuloaciner 2. Mixed with secretions being primarily mucus. Serous exist almost exclusively as demilunes 3. less developed than those of other salivary glands.

Myoepithelial cells (aka basket cells) 1. What are they? 2. What are they made up of? 3. What do they surround? 4. How do they connect to this? 5. What happens when these are contracted?

1. Contractile cells derived from epithelium 2. Actin and myoisin 3. secretory units of many multicellular glands and small ducts. They share the basal lamina with many of these. 4. desmosomes and gap junctions 5. secretion from the gland

Sjogren syndrome: 1. Symptoms 2. How does it happen? 3. demigraphic

1. Dry eyes, dry mouth (hence difficulty swallowing, speaking and tasting), parotid gland enlargement, lymph nodes are enlarged. 2. Salivary and lacrimal glands are infiltrated with CD4 T cells. Serologic marker antibodies are directed against two ribonucleoproteins: SS-A and SSB.

Example of: 1. Unicellular 2. Multicellular sheet 3. Simple acinar 4. Simple branched acinar 5. Simple Tubular 6. Simple coiled tubular 7. Simple branched tubular (2) 8. Compound acinar (2) 9. Compound tubular 10. Compound tubuloacinar (2)

1. Goblet cell 2. Luminal surface of the stomach 3. Paraurethral glands 4. Sebaceous gland 5. Intestinal glands 6. Sweat glands 7. Glands of the stomach and duodenal glands 8. Pancreas and Paroid 9. Bulbourethral glands 10. Submandibular and Sublingual

Intercalated duct, Striated duct and Interlobular ducts. Place in order of drainage to and describe each.

1. Intercalated ducts made of cuboidal epithelium. 2. Striated Duct. Heavily striated and nuclus is pushed up to the duct lumin (center). Also very acidophilic (pink) due to mitochondria. Cuboidal to columnar epithelium 3. Interlobular duct: pseudostratified columnar epithelium. Associated with a lot of connective tissue.

3 types of exocrine glands classified by mode of secretion

1. Merocrine: Via exocytosis and no loss of plasmalemma or cytoplasm. Most common 2. Apocrine: Secretory product is released along with apical cytoplasm and apical plasmalemma (portions pinched off). Lipids are secreted by this method. 3. Holocrine: The entire cell and its secretory product is released. Sebaceous glands are example.

4 Classifications of exocrine glands based on type of secretion

1. Mucous 2. Serous 3. Mixed 4. Sebaceous

2 types of exocrine glands when classified by cell numbers

1. Unicellular: Individual secretory cells found in epithelium. Example is goblet in the GI tube and respiratory membrane 2. Multicellular exocrine glands: May organize into surface exocrine glands with sheets with no secretory tubucles or ducts or into secretory units and ducts.

1.Describe Serous glands 2. Give 2 examples

1. Watery in consistancy and enriched with enzymes. 2. Parotid gland and exocrine pancreas

Mucous glands: 1. What do they secrete? 2. What can mucous form 3. Two examples

1. mucinogens which are large glycosylated, PAS positive proteins that form mucin, a thick protective fluid, when hydrated. Mucin is a component of mucous. 2. Plugs 3. Goblet cells and mucous cells of the stomach

2 major shapes of glands with secretory units

Acinus (alveoulus) Tubular

What do exocrine glands have to do with cancer?

Adenomas (benign) and Adenocarcinomas (malignant) (tumors) develop from glands

What surrounds large multicellular glands. What divides the gland into lobes and lobules

Cellagenous capsule. Septa.

What makes up the intercalated duct?

Centroaciner cells (with large central nuclei) which make up the intraaciner segment of the intercalated duct.

What confirms epithelial lineage of myoepithelial cells?

Cytokeratin which are proteins of keratin-containing intermediate filaments found in the intracytoplasmic cytoskeleton of epithelial tissue

Compound exocrine gland

Ducts are branched

Which usually stains more lightly; secretory portion of gland or ducts? Where is this reversed?

Ducts; Sweat glands

What type of tissue are endocrine glands composed of

Epithelial

What type of tissue are exocrine glands composed of

Epithelial

What type of cell structure are the ducts exocrine products are released from?

Epithelial-lined excretory ducts. Secretions may be modified as they flow through.

What are endocrine glands?

Glands that synthesize and release hormones into the blood to target cells or into extracellular fluid to create autocrine or paracrine effects

Mucous and sebaceous cells tend to look similar. What is the major difference you can see.

Mucous cell nucleus are pushed down toward the basal lamina while sebacceous are dead center.

What hormones affect sebaceous glands?

Sex hormones so benign before puberty. Hence acne shows up.

Simple exocrine gland

Single duct (though may have several secretory portions)

When does the hair shaft penetrate the hair follicle creating an inflammatory response?

With acne. Look for the hair shaft penitrating when looking at it.