Chem unit 4 Liver, cardiac, and renal

What are the two sources of blood for the liver

Hepatic artery (25%) and portal vein (75%)

Where does the portal vein originate from

Intestines

What are the two major cell types in the liver

Hepatocytes and kupffer cells

What are kupffer cells

Macrophages acting as phagocytes

List the breakdown of RBCs

Heme→ biliverdin → indirect bili → direct bili→bile→urobilinogen→urobilin

What is the result of an increase in conjugated bili

Urine bilirubin

What is the result of an increase in unconjugated bili

An increase in urine urobilinogen

Equation for total bilirubin

Indirect+ direct bilirubin

How does the liver work in carbohydrate synthesis

Storing glycogen and degrading glycogen when needed

What is the name of the detoxification and drug metabolism system

Cytochrome P-450 system

What are the two phases of cytochrome P-450

1: addition of polar group

2: sulfation

What coagulation related results are good markers of liver disease

Increased PT and decreased albumin

How does the catabolism of amino acids occur in the liver (what is produced/ what is this converted to)

Ammonia is produced from catabolism and is converted to urea, urea excreted in the kidneys

What is caused by impaired clearance of ammonia

Hyperammonemia and brain damage

What is a porphyria

Defect in heme synthesis (sometimes done by liver)

What color is urine with large amounts of porphyrins

Red or “port wine” color

What porphyrins are tested for in the urine

Porphobilinogens and delta aminolevulinic acid

What is unconjugated bilirubin bound to

Albumin

What happens to unconjugated bilirubin in the liver

It is conjugated and is then water soluble

What drug is a hepatotoxic in excess

Acetaminophen

What is the name of the intermediate metabolite formed during acetaminophen overdose

NAPQI

What is the main effect of alcohol on the liver

Fatty liver disease

NADH is formed during alcohol processing which inhibits fatty acid oxidation leading to excess TAGS (can’t be stored in liver)

What are alcoholics also at risk for

Pancreatitis due to increased triglycerides

What is increased in prehepatic jaundice

Indirect and total bilirubin

What is elevated in hepatic jaundice

Unconjugated and conjugated bilirubin (total)

What is elevated in post hepatic jaundice

Serum conjugated bilirubin, ALP, GGT

What are the lab results for Reye syndrome

Abnormal liver enzymes and elevated ammonia, but bilirubin level is no elevated

What is the name of hepatic jaundice in infants after birth

Kernicterus

What is the main source of error in bilirubin specimens

Exposure to fluorescent light/sunlight

What is used in the jendrassik grof method for measuring bilirubin

Caffeine-benzoate-acetate

What is in aliquot 1 for bilirubin analysis and what does this measure

Diazotized sulfanilic acid and this measured direct (conjugated) bilirubin

What does aliquot 2 contain and what does it measure

Caffeine-benzoate-acetate, this measures total bilirubin by reacting with direct and indirect bilirubin to form azobilirubin

What reagent is used to measure urobilinogen

Ehrlich’s reagent

What does a complete absence of urobilinogen from stool and urine indicate

Complete biliary obstruction

What aminotransferase are elevated in hepatitis

AST and ALT

Which aminotransferase is liver specific

ALT

When is ALP elevated

Biliary tract obstruction, bone disorders

When is 5’NT elevated

Biliary tract obstruction

When is GGT elevated

Liver specific- highest in biliary tract obstruction or alcohol ingestion

Which liver tests measure hepatic synthetics ability

Serum albumin and PT time

Which liver function tests measures nitrogen metabolism

Plasma ammonia levels

What does coronary heat disease manifest as

Myocardial infarction

What does cerebrovascular disease manifests as

Stroke

What does peripheral arterial disease manifests as

Localized pain in arms and legs

What does aortic atherosclerotic disease manifests as

Aneurysms

Cardiac biomarkers are normal in unstable angina, elevated in MI (T/F)

True

What happens to arteries in atherosclerosis

Accumulation of lipids, smooth muscle cells, macrophages, and connective tissue (plaque build up)

What is the development of atherosclerotic plaques called

Atherogenesis

What is a fundamental feature of atherogenesis

Inflammation

What are some of the early biomarkers for MI

LD, CK, flipped LD

When can CK also be elevated

Muscular dystrophy and other skeletal muscle disorders

CK>6% ?

Suggestive of MI

CK<3%?

Suggestive of skeletal muscle damage

What is the calculation for the CK-MB index

CK-MB/total CK activity x100

What are the 3 isoforms of troponin

TnT, TnI, TnC

How do troponin levels change after MI

Rises 4-8 hrs after, peaks at 12-14 hrs, remains elevated for 10 days

What troponin isoforms are preferred for myocardial necrosis

TnI, TnT

When is BNP increased

Congestive heart failure

How does BNP effect blood pressure

Decreases blood pressure by increasing Na and water excretion, causing vasodilation

What is used to monitor endogenous levels of BNP

NT-pro-BNP

What other risk assessment markers are used for MI

high sensitivity CRP, homocysteine levels

What does pulmonary embolism develop from

Deep vein thrombosis

What is often measured for PE

D-dimers

What does D-dimers test

Current or recent coagulation and fibrinolysis

Explain the functions of the PCT, loop of hence, DCT, and collecting ducts

PCT: tubular reabsorption

LOH: aids in reabsorption of water, sodium, and chloride

DCT: adjusts for electrolyte and acid-base regulation, control of ADH and aldosterone

CD: final site for concentration or dilution of urine

How is urea made

Final product of protein catabolism

What is creatinine derived from

Derived from muscle phosphocreatine

What is Uric acid dependent on

Endogenous purine degradation

What happens to non protein nitrogen compounds in renal failure

Urine output decreases, increase in plasma urea and creatinine lvls, decrease in urine urea and creatinine levels

What stimulates ADH secretion

Increased plasma osmolality

What does ADH do

Increase permeability of distal convoluted tubules and collecting ducts to water

What does the kidney synthesize

Renin, EPO, 1,25-dihydroxy vitamin D3, prostaglandins

What is the best test for describing kidney function and for determining GFR

Creatinine clearance

How do you calculate creatinine clearance

What are some other clearance measurements for kidneys

Urea and cystatin C

What does urine osmolality measure

Assesses the concentration ability of kidneys

What does microalbuminuria measure and for what patients is it used for

Small amounts of albumin in the urine, used for diabetes mellitus patients

What is a sign of renal disease in urinalysis

Protein in the urine

What are the lab results for glomerular diseases

Elevated bUN and creatinine, decreased GFR

What are the associated urinalysis results for acute glomerulonephritis, chronic glomerulonephritis , and nephrotic syndrome

AGN: hematuria and proteinuria, RBC casts

CGN: waxy and broad casts, cellular casts

NS: proteinuria, hypoalbuminemia, hyperlipidemia, and lipiduria

What causes renal hypertension

Decreased perfusion to the kidneys