biochem 2 chapter 1

8/6/2019 Biochem 2 Chapter 1

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CHAPTER 1 :PANCREAS

DYSFUNCTIONCLINICAL

BIOCHEMISTRY II(SBD 0113)

MISS SUZAILA BT.ARSAD



ANATOMY OFPANCREAS

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• Pancreas - small organ, approximately six



• 1-2 millions tiny clusters of

cells of endocrine tissue ~Islet of Langerhans

• Acinar cells – exocrinefunction

– Secrete pancreatic enzymes

into pancreatic duct – synthesize and secrete

digestive juices.

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• Islet cells - endocrine function



Islet of Langerhans

• Each islet contains (~2500cells) composed of 4 majorcell types:

– α cells – edge,secrete hormonglucagon

– β cells – centre, secrete

hormon insulin – δ cells – between α & β cells -

secrete hormone GHIH

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F cells – between α cellstowards edge, secrete



Function of pancreas

EXOCRINE

–creates

enzymes

to digest

fats,

protein

and

carbohy

drate.

ENDOCRINE

–for

maintaining

blood

glucose

levels. normal

range : 70

to 150

mg/dL



Digestive Enzymes

The exocrine pancreas secretes the pancreatic juice consisting of two

components:

– Pancreatic enzyme – secreted by the acinar cells that form

the acini. Acinar cells secrete 3 different types

of enzymes. What are they? very important because they can

almost completely digest food inthe absence of all other digestive

secretion.

– Aqueous alkaline solution rich in sodium bicarbonate (NaHCO3) actively secreted by the duct cells

that line the pancreatic ducts.



COMMON PANCREATIC DISEASES cute Pancreatitis

– .Blockage of the pancreatic duct by gallstone

– Can circulate to other body organs causing shock.and organ failure

hronic Pancreatitis

– Associated most often with gall bladder disease and alcoholism

– Lead to other problems such as bacterial.infection and type 2 diabetes

ystic Fibrosis

–Disrupts chloride transport at the cellularlevel



PANCREATIC FUNCTION TEST

Amylase – – one of several pancreatic enzymes

produced by the pancreas to help digestfats, proteins, and carbohydrates.

– secreted through the pancreatic duct into

the duodenum, where it helps break downdietary carbohydrates. – the most common blood test for acute

pancreatitis.

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It increases from 2 to 12 hours after thebeginning of symptoms and peaks at 12 to72 hours.

It may rise to 5 to 10 times the normal leveland will usually return to normal within aweek.

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Amylase

measures the amount of amylase in theblood or urine - usually present in smallquantities.

Eg. When cells in the pancreas injured orpancreatic duct is blocked

amounts of amylase increase into the

bloodstream

increasing concentrations in the bloodand the urine



• Urine VS blood amylaseconcentration

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• urine creatinine clearance may beordered along with the urineamylase to help evaluate kidney

function since decreased kidneyfunction can result in a slower rateof amylase clearance.

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Lipase• enzyme that, along with bile

from liver

• Chronic pancreatitiscells destroyed lipase

production drops to <10%of the normal levelsteatorrhea (fatty, foul-

smelling stools)•



• acute pancreatitis

– very high (2-5X than normal

range) – Rapid and sharp rise within

hours after beginning of attack (4-8 hours,peak 24

hour) – Decline after 4 days

• Low lipase level? – Pancreatic tissue

damage/destruction ….egdisease?

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Trypsinogen

• Proteolytic proenzyme

• Elevated level – during attack

of pancreatitis and renalfailure

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• Decreased level – pancreaticinsufficiency, cystic fibrosisand insulin dependant

diabetes



er es s a may eused to check for

complications of acute

pancreatitis include: • Complete Blood Count

(including white blood cell

count)• Bilirubin, liver function

tests)

• Glucose• Calcium

• C-Reactive Protein (a

measure of inflammation)



Other tests that may be used to check for chronic pancreatitis include:

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Fecal elastase test – measures the levels of elastase, an

enzyme found in fluids produced bythe pancreas.

– Elastase digests (breaks down)proteins.

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• - Trypsinogen (Immunoreactivetrypsin) - a serum test that, whenlow, also detects pancreatic

sufficiency•



Secretin stimulation test

• Secretin

– hormone made by the smallintestines.

– stimulates the pancreas to release afluid that neutralizes stomach acidand aids in digestion

– Prodn of bicarbonate/alkalinepancreatic fluid

• The secretin stimulation testmeasures the ability of the

pancreas to respond to secretin.



• places a tube down the throat, intothe stomach, then into the upperpart of the small intestine.

• Secretin is administered and thecontents of the duodenal secretionsare aspirated (removed with

suction) and analyzed over a periodof about two hours.

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THANK YOU

biochem 2 chapter 1

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