ACCESSORY DIGESTIVE GLANDSLIVER, GALLBLADDER, AND PANCREASLIVER, GALLBLADDER, AND PANCREAS

TO IDENTIFY THE EXOCRINE AND ENDOCRINE FUNCTIONS OF THE LIVER AND PANCREAS

TO IDENTIFY THE EXOCRINE AND ENDOCRINE FUNCTIONS OF THE LIVER AND PANCREAS

TO EXAMINE THE HISTOLOGICAL STRUCTURE OF THE LIVER, GALLBLADDER, AND PANCREAS

TO EXAMINE THE HISTOLOGICAL STRUCTURE OF THE LIVER, GALLBLADDER, AND PANCREAS

TO CORRELATE STRUCTURE AND FUNCTION OF THESE ACCESSORY DIGESTIVE GLANDS

TO CORRELATE STRUCTURE AND FUNCTION OF THESE ACCESSORY DIGESTIVE GLANDS

ACCESSORY DIGESTIVE GLANDSACCESSORY DIGESTIVE GLANDS

ACCESSORY DIGESTIVE GLANDS

PANCREAS

1) EXOCRINE PORTION

2) ENDOCRINE PORTION

ACCESSORY DIGESTIVE GLANDS

PANCREAS

1) EXOCRINE PORTION

2) ENDOCRINE PORTION

- synthesizes and secretes enzymes via a system of ducts that are essential for digestion in the intestine

- synthesizes and secretes hormones into the bloodstream to regulate glucose, lipid, and protein metabolism

ACCESSORY DIGESTIVE GLANDS

PANCREAS

1) EXOCRINE PORTION

- COMPOUND ACINOUS GLAND

- EACH ACINI CONSIST OF 5-8 PYRAMIDAL CELLS THAT SIT ON A BASAL LAMINA AND SURROUND A CENTRAL LUMEN

ACINAR CELLS

- BASALLY LOCATED NUCLEI & RER

- SUPRANUCLEAR GOLGI ZONE

- ZYMOGENIC GRANULES CONTAINING DIGESTIVE ENZYMES IN APICAL REGION

CENTROACINAR CELLS

- LINE LUMEN OF ACINUS

- SECRETE LARGE AMOUNTS OF BICARBONATE

ACCESSORY DIGESTIVE GLANDS

PANCREAS

1) EXOCRINE PORTION

INTERCALATED DUCTS

INTRALOBULAR DUCTS

INTERLOBULAR DUCTS

MAIN DUCTS

PANCREAS H&EPANCREAS H&E

ACCESSORY DIGESTIVE GLANDS

PANCREAS

1) EXOCRINE PORTION

INTERCALATED DUCTSINTERCALATED DUCTS- lined with simple squamous epithelium

INTRALOBULAR DUCTSINTRALOBULAR DUCTS

- lined with simple cuboidal epithelium

- size on the order of magnitude of acini

INTERLOBULAR DUCTSINTERLOBULAR DUCTS

- lined with simple columnar epithelium

- found in fibroconnective tissue septa

ACCESSORY DIGESTIVE GLANDS

PANCREAS

1) EXOCRINE PORTION

ACINAR CELLS

- BASALLY LOCATED NUCLEI & RER

- SUPRANUCLEAR GOLGI ZONE

- ZYMOGENIC GRANULES CONTAINING DIGESTIVE ENZYMES IN APICAL REGION

CENTROACINAR CELLS

- LINE LUMEN OF ACINUS

- SECRETE LARGE AMOUNTS OF BICARBONATE

trypsinogen, amylase, lipasetrypsinogen, amylase, lipase

ACCESSORY DIGESTIVE GLANDS

PANCREAS

1) EXOCRINE PORTION

INTERCALATED DUCTS

PANCREAS H&EPANCREAS H&E

ACCESSORY DIGESTIVE GLANDS

PANCREAS

1) EXOCRINE PORTION PANCREAS H&EPANCREAS H&E

EXO-EXO-ENDO-ENDO-

2) ENDOCRINE PORTION

ACCESSORY DIGESTIVE GLANDS

PANCREAS

2) ENDOCRINE PORTION

- PRINCIPLE FUNCTION IS TO SECRETE HORMONES THAT REGULATE BLOOD GLUCOSE LEVELS

ISLETS OF LANGERHANS

- MASSES OF RICHLY VASCULARIZED ENDOCRINE CELLS SCATTERED THROUGHOUT THE PANCREAS

- SEPARATED FROM SURROUNDING ACINAR CELLS BY THIN CAPSULE OF RETICULAR FIBERS

- 3 CELL TYPES IN ISLET DISTINGUISHED ONLY VIA SPECIAL STAINS

ACCESSORY DIGESTIVE GLANDS

PANCREAS

2) ENDOCRINE PORTION

ACCESSORY DIGESTIVE GLANDS

PANCREAS

2) ENDOCRINE PORTION

CELL TYPES:

1) ALPHA CELLS (20%)

2) BETA CELLS (75%)

3) DELTA CELLS (5%)

- SECRETE GLUCAGON; RAISES BLOOD GLUCOSE LEVELS

- SECRETE INSULIN; LOWERS BLOOD GLUCOSE LEVELS

- SECRETE SOMATOSTATIN; INHIBITS GLUCAGON AND INSULIN SECRETION

ACCESSORY DIGESTIVE GLANDS

LIVER

1) EXOCRINE PORTION

2) ENDOCRINE PORTION

- synthesizes and secretes bile via a system of ducts that is essential for digestion in the intestine

- synthesizes and secretes numerous plasma proteins into the bloodstream: (albumin, fibrinogen, prothrombin, lipoproteins, etc.)

ACCESSORY DIGESTIVE GLANDS

LIVER

PORTA HEPATIS

PORTAL TRIAD

ACCESSORY DIGESTIVE GLANDS

LIVER

Classical Liver Lobule

- basic functional unit of liver

ACCESSORY DIGESTIVE GLANDS

LIVER

CLASSIC LOBULE PORTAL LOBULE LIVER ACINUS

- central vein at center

- hexagonal in shape

- portal triad at corners

- portal triad at center

- triangular in shape

- central vein at corners

- short axis: branches of portal triad between 2 classic lobules

- long axis: between 2 central veins

ACCESSORY DIGESTIVE GLANDS

ACCESSORY DIGESTIVE GLANDS

ACCESSORY DIGESTIVE GLANDS

LIVER

1 HEPATOCYTES

2 SINUSOIDS

3 SPACE OF DISSE

4 BILE CANALICULI

ACCESSORY DIGESTIVE GLANDS

LIVER

1 HEPATOCYTES

2 SINUSOIDS

3 SPACE OF DISSE

4 BILE CANALICULI

- perisinusoidal space between basal surfaces of the endothelial cells and the surfaces of the hepatocytes

- small canal beginning the biliary tree formed by apposed grooves in adjacent hepatocytes

LIVERLIVER

ACCESSORY DIGESTIVE GLANDS

LIVER

LIVER H&ELIVER H&E

PV

HA

BD

ACCESSORY DIGESTIVE GLANDS

LIVER

BILE DUCTSBILE DUCTS- lined with simple cuboidal epithelium

ACCESSORY DIGESTIVE GLANDS

LIVER LIVER H&ELIVER H&E

1 HEPATOCYTES

2 SINUSOIDS

ACCESSORY DIGESTIVE GLANDS

LIVER LIVERLIVER

RETICULAR FIBER MESHWORK

ACCESSORY DIGESTIVE GLANDS

LIVER

RETICULAR FIBER MESHWORK

KUPFFER CELLS

- phagocytic cell, liver macrophage

ACCESSORY DIGESTIVE GLANDS

LIVER

KUPFFER CELLS

CV

LIVER H&ELIVER H&E

ACCESSORY DIGESTIVE GLANDS

LIVER

KUPFFER CELLS

LIVER H&ELIVER H&E

ACCESSORY DIGESTIVE GLANDS

LIVER

3-D APPRECIATION FOR HISTOLOGICAL STRUCTURE OBSERVED IN 2-D

ACCESSORY DIGESTIVE GLANDS

LIVER

3-D LOOK AT THE BILIARY SYSTEM3-D LOOK AT THE BILIARY SYSTEM

ACCESSORY DIGESTIVE GLANDS

LIVERLIVER H&ELIVER H&E

SITE OF HEMOPOEISIS DURING EARLY GESTATION

SITE OF HEMOPOEISIS DURING EARLY GESTATION

ACCESSORY DIGESTIVE GLANDS

LIVERLIVER H&ELIVER H&E

SITE OF HEMOPOEISIS DURING EARLY GESTATION

SITE OF HEMOPOEISIS DURING EARLY GESTATION

ACCESSORY DIGESTIVE GLANDS

GALLBLADDER

ROUTE OF BILE

HEPATOCYTE

BILE CANALICULI

RT & LT HEPATIC DUCTS

COMMON BILE DUCT

FILLING OF GALLBLADDER

- LOCATION FOR CONCENTRATION AND STORAGE OF BILE

ACCESSORY DIGESTIVE GLANDS

GALLBLADDER

THREE LAYERS:

1) MUCOSA

- lined with tall columnar epithelium and underlying basal lamina & lamina propria

- mucosa highly folded and irregular

2) MUSCULARIS EXTERNA

- layers of smooth muscle with irregular orientation

3) ADVENTITIA or SEROSA

- NO MUSCULARIS MUCOSA OR SUBMUCOSA -

ACCESSORY DIGESTIVE GLANDS

GALLBLADDER

EPITHELIUM:

- tall columnar epithelium and underlying basal lamina & lamina propria

- basally located nuclei

- fine microvilli border