Pancreas and Liver Microanatomy Flashcards Preview

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Flashcards in Pancreas and Liver Microanatomy Deck (41)
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1

How is the pancreas structured

lobules with ducts

2

Appearance and structure of exocrine pancreatic cells

Dark staining (due to zymogen granules). Granular appearance
Arranged as pancreatic acini

3

Appearance and structure of endocrine pancreatic cells

Light/pale staining cells, arranged in clusters, embedded among exocrine cells.
Form Islets of Langerhans

4

Function of Ductule cells

To produce HCO3-

5

Function of exocrine pancreatic cells

to produce digestive enzymes, fluids and electrolytes

6

Function of the endocrine pancreatic cells

Produce hormones to control blood sugar

7

exocrine pancreatic gland?

tubulo-acinar gland with highly branched ducts

8

What is the exocrine pancreatic gland similar to?

parotid gland (serous)

9

Acini

contain 5-8 pyramid-shaped cells surrounding a tiny lumen.
Large spherical nucleus in the basal position
Mitochondria perpendicular to the basal surface.

10

How tiny is the pancreatic acinar lumens?

Too small to see with a light microscope

11

where are protein secretory products (enzymes) synthesised in the pancreas

Basal rER, packaged in the golgi, and accumulated as zymogen granules in the apical cytoplasm of exocrine acinar cells.

12

Acini produce

A small volume of enzyme rich fluid.

13

Duct cells produce

Bicarbonate and a large volume of alkaline fluid ~1L/day

14

What is the path of product drainage from the acini to the duodenum?

intercalated ducts > intralobular ducts > interlobular ducts > pancreatic duct > Ampulla of Vater > duodenum

15

Intercalated duct cells that penetrate the lumen of acini are called?

Centro-acinar cells'

16

Some Liver functions

Exocrine
endocrine
synthesis (albumin, prothrombin, bile)
storage (glycogen)
detoxification

17

What runs between the radiating columns of hepatocytes, and what is their function

Sinusoids. (special capillary)
Carry the mixed blood flow from branches of the portal vein/ hepatic artery to drain into the central vein.
As blood flows through sinusoids oxygen and nutrients are diffused into adjacent hepatocytes down their concentration gradient.

18

What lines the sinusoids?

Kupffer cells.

19

The central veins position, purpose and journey.

Position: Centre of liver lobule
Purpose: collects blood from the lobule sinusoids
Journey: Central veins collect > hepatic veins > IVC

20

Why are the sinusoids arranged the way they are?

To ensure maximal exposure of the hepatocytes to a blood supply.
Ensure a good supply of nutrients, keeps them nourished

21

What encases the liver lobules?

Interlobular Septa
made of CT
-with collagen, BV's and nerves

22

What are liver lobules meant to look like?

a hexogonal shape, but this often isn't the reality

23

Classical anatomical shape within the liver

hexagonal shape. Formed by the hepatic lobule. Each edge has a portal space

24

Functional unit of the liver?

Liver acinus.
Diamond that radiates from the branches interlobular septa/portal triad out to the central veins.

25

Portal lobule looks like?

Triangle (points are the central veins). The bile drains through canaliculi in the hepatocytes to the bile duct.

26

Portal space contains

CT and a portal triad

27

Branch of the Hepatic portal vein under the microscope looks?

-thin walled
-large lumen (therefore low pressure)

28

Branch of the Hepatic artery proper looks like

thicker muscular wall
relatively smaller lumen (therefore higher systemic pressure)

29

Contribution of blood to the liver?

75% From hepatic portal vein (nutrient rich)
25% from Hepatic artery Proper (oxygen rich)

30

path of blood from a branch of the portal vein to the IVC

branch of portal vein > {intermediates} > lobule sinusoid > central vein > (hepatic vein > collecting vein > intercalated vein) > IVC