Protien Catabolism & Nitrogenous Waste Excreation Flashcards
Functions of EPO?
Anti apoptosis function
Produce more RBC 
_____________ recycles HCO3
Kidneys
How can kidney disease lead to lysed RBCs?
Decreased EPO—> anemia and decreased bicarb ——> acidosis ——> causes membrane damage of RBCs and ruptures the cells
What is the most abundant serum protein?
Albumin
What is A:G ratio?
Albumin : total globulin
NPNs…
Non-protein
-cholesterol
-glucose
-urea nitrogen
-uric acid
-creatinine
-iron
Albumin range
3.4-5.0 g/dl
Total globulin range
2.2- 4.0 g/dl
Transferrin
250 mg/dl
Haptoglobin range
30- 205 mg/ dl
Ceruloplasmin range
25-45 mg/dl
Ferritin range
15- 300 ug/ dl
Hemopexin range
50- 100 mg/dl
Cholesterol range
140-250 mg/dl
Glucose range
70- 110 mg/dl
Urea nitrogen
6-23 mg/dl
Uric acid range
4.1- 8.5 mg/dl
Creatinine range
0.7- 1.4 mg/dl
Iron range
50-150 ug/dl
What can be a source of oxidative stress when not bound?
Haptoglobin when not bound to alpha globin chain
Free haptoglobin ______ can tell if if alpha is defective
G
_____________ becomes toxic when not bound
Transferrin
-can bind to free heme
-delivered to liver to be recycled
Haptoglobin
Hemopexin
Source of NPNs
Amino acids
Urea is synthesized in the ___________ from NH3 (Bacterial metabolism and got it and AA deamination) 
Liver
More protein ———-> more _____________ in GI.
Ammoniagesin
Why is determination important metabolic process?
Allows product (protein?) to be used for energy or to be converted into carbs or fat
urea in circulation is reported as ….
Blood urea nitrogen (BUN) 
BUN is increased with….
High protein diets and tissue breakdown
BUN is decreased with…
Protein synthesis, chronic and progressive renal insufficiency (No reabsorption), low protein intake and severe liver disease
Urea filtered in the kidney (______% reabsorbed in collecting duct, ____% excreted in urine)
40-50
50-60
Because BUN increased or decreased while GFR is normal, BUN is a _____________ Indicator of renal function.*****
Nonspecific **
(Compared to other markers) 
C.f. Urea production > Urea excretion: Urea remains in system —-> Degraded to ______ by intestinal bacteria and process by liver and cleared.
NH4
What is the most abundant NPN?
BUN
What are the three types of acute renal failure?
-Prerenal (Hypovolemia or poor perfusion) Before kidneys
-Renal (Rapid deterioration, e.g. Acute tubular necrosis) at kidneys
-post Renal (Obstructions, When osmolarity becomes the same in blood and tubule Filtration stops) After kidneys 
Pre-renal acute failure is usually due to altered ____________ function. 
Cardiovascular
(given ACE or angiotensin)
In normal serum, what is the year BUN/urea: Creatinine ratio? ***
10:1 - 20:1*
If both BUN and creatinine is elevated, ratio will still be normal bit could indicate…
Renal disease
- Both can be out of range but have normal ratios
What is the most common cause of increased BUN in middle aged men? 
G.I. bleeding
What can cause an abnormal urea to creatine ratio?
Increase amino acid breakdown as in muscle wasting, high protein diet or G.I. bleeding
Serum BUN serum creatinine ratio greater than 20:1 Is observed in patients with…
• pre-renal azotemia*** (Accumulation of nitrogenous products in blood)
• Gastrointestinal bleeding
• Excessive protein intake
-Post-renal azotemia
BUN is absolute for determining renal function. true or false?
False! 
What is used to determine urea BUN ratio? 
-Berthelot reaction
-enzymatic glutamate dehydrogenase (340nm)
-Conductance
-protentiometric
-diacetyl monoxime
-O-phthalaldehyde 
-absorption maximum measured at 560 nm
-Performed directly on blood, serum or urine
Berthelot Reaction (rarely used)
(Urea methodology) 
Why is Berthelot Reaction rarely used? What’s the disadvantage?
Difficult to automate, lack of specificity, beers law narrow range
Beers law?
A =  epsilon b c ?
Berthelot Reaction test can be monitored at _____nm and Produces a bluish color from indophenol complex
560
-Method used quite frequently in clinical labs
-Conductivity increases with formation of
Urea ——Urease —->(NH,),COg —->2NH, +CO,
-Conductively measured at the same time
Conductance (Urea methodology)
-NH3 ISE Monitors urease reaction
-Urease covalently linked to electrode, converts urea to NH3
-Change in pH measured by electrode
-Very specific but not commonly use due to possibility of contamination***
UREA METHODOLOGY: POTENTIOMETRY
-Direct chemical analysis of urea (Instead of using urease)
-Commonly used
***Diacetyl Monopxime (urea methodology) 
Reference interval (BUN) for Diacetyl Monopxime?
8-26 mg/dl
(A lot of fluctuation in numbers, lab sets their own range) 
What is the disadvantage of Diacetyl Monopxime?
-Photosensitivity of product
-large dilution of sample required for beers law
-Corrosive reagents
Diacetyl Monopxime:
Yellow Diazine
-chromagen _____nm
-Fluorescence _____ nm 
550
415
no use of enzymes in this test
-Rarely used because of interference with other primary amines
O-phthalaldehyde*
A group of atoms and electrons forming part of an organic molecule that causes it to be colored
Chromophore
(At 510 nm with O-phthalaldehyde)
Why is O-phthaladehyde rarely used for urea? 
Interference with other primary amines 
What are the benefits of using dry slide urease-pH indicator?
-excellent accuracy
-Little interference from other biochemicals
- Commonly used and can use different dyes 
What specimen is used for urea testing?
Serum or heparinized plasma or diluted urine
When testing for urea, CANNOT use ___________ (Inhibits urease reaction) or ___________ (Causes artificial elevation)
Fluoride, NH4 heparin***
What is the storage requirements for urea?
serum and plasma is stable for one week at 4°C or six months at -20°C
Creatinine is proportional to…
Muscle mass
What lab marker is important in liver disease?
Creatinine
CK requires ______. It is important for diagnosis of many diseases (ex: CK1, CK2, CK3)
ATP
Creatinine is formed from __________ creatine and creatine ________.**
Muscle
Phosphate
Creatinine in serum is proportional to…
Muscle mass. Generally increased in males compared to females
Serum concentrations of creatinine depends on?
-rate of production
-Rate of removal
*** Does not change dramatically, very stable!
There is little effect on serum creatinine from diet, urine volume and exercise
-plasma creatinine is stable with less than 10% variation in a day because….
-concentration in muscle is constant
-Rate of spontaneous breakdown is constant
Measure _____________ Clearance to determine filtration GFR**
Creatinine
How is creatinine filtered in the kidneys?Is creatinine reabsorbed?
-Freely filtered
-Not REABSORBED (5 to 20% may be secreted, from tubular secretion, not filtration)
- Urinary excretion is directly proportional to muscle mass

About _____ mmol/creatinine excreted/kg of muscle mass
5
Exercise __________ Increases creatinine in serum and or urine
Slightly
Protein deficiency long-term ___________ Decreases creatinine in serum
Decreases