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28 Cards in this Set
- Front
- Back
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list the essential aa's
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Private Tim Hall
PVT TIM _H(A)LL phe val trp thr iso met his arg leu lys |
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what is special about his and arg
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his=does not fulfill all criteria for being indispensible
arg = essential only under extreme circumstances |
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livr failure, want to increase or decrease aa consumption
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decrease to avoid hepatic trauma
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fractures, want to increase or decrease aa
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increase
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eating disorders, increase or decrease aa consimption
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increase
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uremia increase or decrease aa consumption
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decrease, aa will be metabolized for energy or gluconeogenesis and nitrogen will be stripped off and incorporated into urea
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how do you measure protein metabolism
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BUN blood urea nitrogen
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poor or high quality protein generates a higher BUN
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poor, because wrong mix of aa's, excess aa's will be metabolized increasing blood urea nitrogen
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where are proteins absorbed
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abs as aa and di/tri peptides along entire small intestine, but more at proximal end
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draw out dietary protein going from stomach to small intestine, and where enzymes come in
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stomach - polypeptides unwound and partially degraded by pepsin and low pH
small intestine: enteropeptidase on brush border pancrease secretes trypsin, chymotripsen, elastase, and carboxypeptidase in the zymogen form peptides are cleaved to 40% free aa and 60% oligopeptides |
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how does absorption of free aa and oligopep's work
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free aa - symport with Na
di and tri peptides = symport with H+ |
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Uptake of aa from blood
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mainly by liver, which catabolizes 57% converts 20% to protein and releases 23%
most released aa are BCAA insulin decreases plasma BCAA by stimulating uptake in muscles |
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what are the primary energy sources of enterocytes?
what aa do enterocytes generate? |
E = glutamine
generate = alanine |
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enterocytes synthesize
4 |
1) export proteins (apolipoprotein for lipoprotein formation)
2) glutathione - GSH 3) non essential aa's 4) intermediates of urea cycle |
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in a healthy adult if 100 g protein ingested, to be in balance, 100 g have to be excreted in stool(about 10) or catabolized(about 90)
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aa are catabolized to CO2 and nitrogen, nitrogen=urea
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1 gram of nitrogen comes from how many grams protein?
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6.25
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Nitrogen balance equation
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Intake - (urine + Feces + skin)
Nitrogen balance = protein N intake(g/24h) - (urinary urea N + 4g) |
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protein balance equation
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protein intake(g) - [(urinary urea N + 4)X 6.25
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a positive nitrogen balance means more intake or more loss
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more intake
during periods of growth or pregnancy negative during starvation sickness etc |
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PEM
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Protein energy malnutrition: spectrum of states of malnutrition
Kwashiorker mildest in anthropomorphic changes Marasmus more severe anthro changes |
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Kwashiorker
adapted or nonadapted starvation adequate caloric intake? major symptoms |
non-adaptive starvation
caloric intake may actually be adequate or nearly adequate, protein intake is not symptoms: EDEMA (intra and extracellular) hair changes, skin disorders, hepatomegaly, hypoalbumin |
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Kwashiorker
what happens to liver? |
b/cms fatty because of increased FA synthesis
cant produce apolipoproteins for lipid transport cause no aa's |
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severe weight loss associated with chronic diseases like cancer is called?
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cachexia
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back to kwashiorker
muscle protein broken down or not? |
non adaptive PEM
dietary carbohydrate insulin levels are maintained and muscle protein is not broken down to generate glucogenic amino acids but DO have significant negative nitrogen balance |
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explain edema in kwashiorker, why do you get it
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liver is unable to maintain blood levels of albumin, and osmotic balance is disturbed, causing fluid to accumulate in extracellular spaces
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explain hepatomegaly in kwashiorker
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Can't make aoplipoproteins(LDL etc), Triglyceride made in the liver cannot become packaged with protein for export, and accumulates in the liver.
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how much protein is in human plasma
how much of this is albumin |
7.5 g of protein per 100 ml
about 1/2 to 2/3 is albumin |
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how would you assess PEM
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mild: 2.8-3.5 albumin g/Dl
moderate: 2.1-2.7 severe: less than 2.1 |
