Biochemistry of the Liver and Kidney. Urine Formation

7/27/2019 Biochemistry of the Liver and Kidney. Urine Formation.

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LECTURE ON BIOLOGICAL CHEMISTRY FOR 2 YEAR STUDENTS

OF MEDICAL FACULTY ( 2005- 2006)

LECTURE 23

THEME: BIOCHEMISTRY OF THE LIVER AND KIDNEY URINE

FORMATION

!LAN OF LECTURE

" B#$%$'% *+',#$+ $ ,./ %#/1

2 R$%/ $ ,./ %#/1 #+ '1$.41,/ /,$%#.

3 R$%/ $ ,./ %#/1 #+ %##4 /,$%#

7 R$%/ $ ,./ %#/1 #+ 1$,/#+ /,$%#

5 R$%/ $ ,./ %#/1 #+ 4/,$8##',#$+ 1$'//

6 B#$%$'% *+',#$+ $ ,./ 9#4+/

M/'.+# $ *1#+/ $1,#$+

; R/+% 1/&*%,#$+ $ 1,/1#% %$$4 1/*1/


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Liver(!upffer cells)can remove foreign bodies from blood by phagocytosis. "t can

detoxify various drugs and hormones by converting them into less toxic substances

which are excreted.

4. Storage FunctionsLiver stores glucose in the formof glycogen."t is also responsible to some

extent for the storage of some vitamins e.g vitamin Aand #$.

5. Syntesis o! "lood #oagulation Factors

%reprothrombin (inactive form) is converted into prothrombin in liver in the

presence of vitamin !. &ther coagulation factors e.g. factor ', '"" and are also

synthesied in the liver.

$. %xcretory Functions

romosulphthalein (*%) and +ose engal dye are exclusively found to be

excreted through liver cells.

&. 'andling o! %n(ymes

uch significance is attributed to liver for handling of enymes like alkaline

phosphatase (-L%) and release of transaminases e.g. aspartate transaminase (&/)and alanine transaminase (%/).

). Miscellaneous Functions

(a) lood formation in embryo.

(b) lood formation in adults in some abnormal states.

R$%/ $ ,./ %#/1 #+ '1$.41,/ /,$%#.

0rom intestine glucose pass into the liver, where most part of it undergoes the

phosphorylation. lucose121phosphate is formed as result of this reaction, which is

catalyed by two enymes 3 hexokinase and glucokinase. 0ructose and galactose also

are transformed into glucose121phosphate in the liver.

lucose121phosphate is a key product of carbohydrates metabolism. "n the liver

this substance can metabolied into different ways depend of liver4s and whole

organism4s necessity.


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#. *ynthesis of glycogen. Content in the liver 3 561#66g. -fter eating amount

of glycogen in the liver increase up to #76g. -fter $8 hours of starvation content of

glycogen in the liver decreases to ero and glukoneogenesis started.

$. lucose121phosphatase catalie dephosphorylation of glucose121phosphate

and free glucose is formed. /his enyme is present in the liver, kidney and small

intestine. /his process maintain normal level of glucose in the blood.

9. xcess of glucose121phosphate, which is not used for the synthesis of

glycogen and formation of free glucose, is decomposed in glycolysis for pyruvate and

for acetyl1Co-, which are used for fatty acids synthesis.

8. lucose121phosphate is decomposed for ;$& and C&$, and free energy for

hepatocytes is formed.

7. %art of glucose121phosphate is oxidied in pentosophosphate cycle. /his way

of glucose decomposition supplyes reducted 9 3 for glycolisis.

;epatocytes content full set of gluconeogenesis necessary enymes. *o, in

liver glucose can be formed from lactate, pyruvate, amino acids, glycerine.

luconegenesis from lactate takes place during intensive muscular work. Lactate is

formed from glucose in muscles, transported to the liver, new glucose is formed and

transported to the muscles (!ori cycle).

R$%/ $ ,./ %#/1 #+ %##4 /,$%#

/he lipid content of liver is about 7?, but all processes of lipid metabolism

take place there. ost important of them are following:

#. Lipogenesis (synthesis of fatty acids and lipids). *ubstrate for this process 3

acetyl1Co-, formed from glucose and amino acids, which are not used for another

purposes. /his process is very active when the person eats a lot of carbohydrates.

Liver synthesies saturated and monounsaturated fatty acids more active than another

tissues. 0atty acids then are used for the synthesis of lipids, phospholipids,

cholesterol ethers. lycerol191phosphate, which is necessary for lipids synthesis,is

formed in liver in result of two processes: from free glycerol under influence of


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glycerolkinase, or in reducing of dioxiacetone phosphate under influence of

glycerolphosphate dehydrogenase. -ctive form of fatty acids interact with glycerol191

phosphate and phosphatidic acid is formed, which used for synthesis of

triacylglycerines and glycerophospholipids.

$. Liver play a central role in the synthesis of cholesterol, because near @6 ?

of its amount is synthesied there. iosynthesis of cholesterol is regulated by

negative feedback. Ahen the level of cholesterol in the meal increases, synthesis in

liver decreases, and back to front. esides, synthesis is regulated by insulin and

glucagon. Cholesterol is used in the organism for building cell membranes, synthesis

of steroid hormones and vitamin =. xcess of cholesterol leads out in the bile to the

intestine. -nother part of cholesterol is used for bile acids synthesis. /his process is

regulated by reabsorbed bile acids according to negative feedback principles.

9. Liver is a place of ketone bodies synthesis. /hese substances formed from

fatty acids after their oxidation, and from liver transported to another tissues, first of

all to the heart, muscles, kidneys and brain. /hese substances are main source of

energy for many tissues of our organism excepting liver in normal conditions (heart)

and during starvation (brain).

R$%/ $ ,./ %#/1 #+ 1$,/#+ /,$%#.

Liver has full set of enymes, which are necessary for amino acids metabolism.

-mino acids from food are used in the liver for following pathways:

#. %rotein synthesis.

$. =ecomposition for the final products.

9. /ransformation to the carbohydrates and lipids.

8. "nteraction between amino acids.

7. /ransformation to the different substances with amino group.

2. +elease to the blood and transport to another organs and tissues.

/he high speed of protein synthesis and decomposition is typical for the liver.

;epatocytes catch different protein from blood (from hemolysated +C, denaturated

plasma proteins, protein and peptide hormones) and decompose them to the free

amino acids which are used for new synthesis. Ahen organism does not get necessary


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Buantity of amino acids from food, liver synthesies only very necessary proteins

(enymes, receptors).

Liver synthesies about #66 ? of albumines, 6 ? of D#1globulines, 57 ? of

D$1globulines, 76 ? of E1globulines, blood clotting factors, fibrinogen, protein part of

blood lipoproteins, such enyme as cholinesterase. /he speed of these processes is

enough high, for example, liver synthesies #$1#2g of albumines per day.

-mino acids, which are not used for protein synthesis, are transformed into

another substances. &xidative decomposition of amino acids is main source of energy

for liver in normal conditions.

Liver can synthesie non1essential amino acids.

Liver synthesies purine and pyrimidine nucleotides, hem, creatin, nicotinic

acid, cholin, carnitin, polyamines.

R$%/ $ ,./ %#/1 #+ 4/,$8##',#$+ 1$'//.

- xenobiotics is a compound that is foreign to the body. /he principal classes

of xenobiotics of medical relevance are drugs, chemical cancerogens, and various

compounds that have found their way into our environment by one route or another

(insecticides, herbicides, pesticides, food additions, cosmetics, domestic chemical

substances). ost of these compounds are subFect to metabolism (chemical

alteration) in the human body, with the liver being the main organ involvedG

occasionally a xenobiotics may be excreted unchanged.

*ome internal substances also have toxic properties (for example, bilirubin,

free ammonia, bioactive amines, products of amino acids decay in the intestine).

oreover, all hormones and mediatores must be inactivated.

+eactions of detoxification take place in the liver. ig molecules like bilirubin

excreted with the bile to intestine and leaded out with feces. *mall molecules go to

the blood and excreted via kidney with urine.

/he metabolism of xenobiotics has $ phases:

I+ ./ ", the maFor reaction involved is hydroxylation, catalyed by

members of a class of enymes referred to as monooxygenases or cytochrome %1876

species. /hese enymes can also catalye deamination, dehalogenation, desulfuration,


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epoxidation, peroxidation and reduction reaction. ;ydrolysis reactions and non1%1

8761catalyed reactions also occur in phase $.

I+ ./ 2, the hydroxylated or other compounds produced in phase # are

converted by specific enymes to various polar metabolites by conFugation with

glucuronic acid, sulfate, acetate, glutathione, or certain amino acids, or by

methylation.

/he overall purpose of metabolism of xenobiotics is to increase their water

solubility (polarity) and thus facilitate their excretion from the body via kidney.'ery

hydrophobic xenobiotics would persist in adipose tissue almost indefinitely if they

were not converted to more polar forms.

"n certain cases, phase # metabolic reaction convert xenobiotics from inactive

to biologically active compounds. "n these instances, the original xenobiotics are

referred to as prodrugs or procarcinogens. "n other cases, additional phase # reactions

convert the active compounds to less active or inactive forms prior to conFugation. "n

yet other cases, it is the conFugation reactions themselves that convert the active

product of phase # to less active or inactive species, which are subseBuently excreted

in the urine or bile. "n a very few cases, conFugation may actually increase the

biologic activity of a xenobiotics.

;ydroxylation is the chief reaction involved in phase #. /he responsible

enymes are called monooxygenases or cytochrome %1876 species. /he reaction

catalyed by a monooxygenase is:

RH + O2+ NADPH + H+ R-OH + H2O + NADP

+; above can represent a very widee variety of drugs, carcinogens, pollutants,

and certain endogenous compounds, such as steroids and a number of other lipids.

Cytochrome %1876 is considered the most versatile biocatalyst known. /he

importance of this enyme is due to the fact that approximately 76 ? of the drugs that

patients ingest are metabolied by species of cytochrome %1876. /he following are

important points concerning cytochrome %1876 species:

#. Like hemoglobin, they are hemoproteins.


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$. /hey are present in highest amount in the membranes of the endoplasmic

reticulum (+) (microsomal fraction) of liver, where they can make up approximately

$6 ? of the total protein. /hay are also in other tissues. "n the adrenal, they are found

in mitochondria as well as in the +G the various hydroxylases present in that organ

play an important role in cholesterol and steroid biosynthesis.

9. /here are at least 2 closely related species of cytochrome %1876 present in

liver +, each with wide and somewhat overlapping substrate specificities, that act

on a wide variety of drugs, carcinogens, and other xenobiotics in addition to

endogenous compounds such as certain steroids.

8.


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"n phase # reactions, xenobiotics are generally converted to more polar,

hydroxylated derivates. "n phase $ reactions, these derivates are conFugated with

molecules such as glucuronic acid, sulfate, or glutatione. /his renders them even

more water1soluble, and they are eventually excreted in the urine or bile.

/here are at least 7 types of phase $ reactions:

" G%*'*1$+#4,#$+H=%1glucuronic acid is the glucuronyl donor, and a

variety of glucuronyl transferases, present in both the + and cytosol, are the

catalysts. olecules such as bilirubin, thyroxin, $1acetylaminofluorene (a

carcinogen), aniline, benoic acid, meprobromate (a tranBuilier), phenol, creol,

indol and skatol, and many steroids are excreted as glucuronides. /he glucuronide

may be attached to oxygen, nitrogen, or sulfur groups of substrates. lucuronidation

is probably the most freBuent conFugation reaction.

2 S*%,#$+*ome alcohols, arylamines, and phenols are sulfated. /he sulfate

donor in these and other biologic sulfation reactions is adenosine 9I1phosphate17I1

phosphosulfate (%-%*)G this compound is called active sulfate.

3 C$+>*&,#$+ ?#,. G%*,,.#$+/lutathione (J1glutamylcysteinylglycine) is

a tripeptide consisting of glutamic acid, cysteine, and glycine. lutathione is

commonly abbreviated to *;G the *; indicates the sulfhydryl group of its cysteine

and is the business part of the molecule. - number of potentially toxic electrophilic

xenobiotics (such as certain carcinogens) are conFugated to the nucleophilic *;.

/he enymes catalying these reactions are called glutathione *1transferases and are

present in high amounts in liver cytosol and in lower amounts in other tissues.

glutathione conFugates are subFected to further metabolism before excretion. /he

glutamyl and glycinyl groups belonging to glutathione are removed by specific

enymes, and an acetyl group (donated by acetyl1Co-) is added to the amino group

of the remaining cystenyl moiety. /he resulting compound is a mercapturic acid, a

conFugate of L1acetylcysteine, which is then excreted in the urine.

8. A'/,%,#$+/hese reactions is represented by @ A'/,%-C$A A'/,%-@

C$A, where represents a xenobiotic. /hese reactions are catalyed by

acetyltransferases present in the cytosol of various tissues, particularly liver. /he


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different aromatic amines, aromatic amino acids, such drug as isoniaid, used in the

treatment of tuberculosis, and sulfanylamides are subFects to acetylation.

%olymorphic types of acetyltransferases exist, resulting in individuals who are

classified as slow or fast acetylators, and influence the rate of clearance of drugs such

as isoniaid from blood. *low acetylators are more subFect to certain toxic effects of

isoniaid because the drug persists longer in these individuals.

7. M/,.%,#$+- few xenobiotics (amines, phenol, tio1substances, inorganic

compounds of sulphur, selen, mercury, arsenic) are subFect to methylation by

methyltransferases, employing *1adenosylmethionine as methyl donor. -lso

catecholamines and nicotinic acid amid (active form of vitamin %%) are inactivated

due to methylation.

B#$%$'% *+',#$+ $ ,./ 9#4+/

/he kidneys are paired organs, which are responsible for the constancy of the

internal environment in the organism and elimination of the metabolism end1

products./he kidneys regulate water1electrolyte balance, acid1base balance, excretion

of metabolic wastes, osmotic pressure. esides, they take part in the regulation of

blood pressure and +..C production

ach kidney is composed of $ layers: the cortex or outer layer is brownish1 red

and the medulla or inner layer is lighter in colour. /he nephron is the functioning unit

of the kidney. ach kidney contains more than a million of nephrons.

"t consists of renal corpuscle, which contains glomerulus surrounded by hollow

capsule (owman4s capsule). esides each nephron contains: proximal convoluted

tubules, a descending limb of the loop of ;enle, collecting tubules and distal

convoluted tubules.

/he $ principal types of nephron are classified according to their position in the

kidneys:

#. Cortical nephrons (@7?), which are situated in the cortex.

$. Kuxtamedullary nephrons (#7?)

/he kidneys are the main organs of the elimination. /hey take part in the

elimination of the end1products of proteins metabolism, water and salts. /he kidneys


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are the most important organs of excretion. - human dies when the kidneys are not

functioning for 812 days.

/he kidneys4 tissue contains a lot of water (about @8? ). /he kidneys absorbe

approximately #6? of the oxygen, which is used by the organism.

566166 l of blood passes through the kidneys per day.

Carbohydrates are basic energetic materials for the work of kidneys.

!etolysis, glycolysis, aerobic oxidation and phosphorylation take place in the

kidneys. -erobic metabolism dominates in the cortex, and in medulla 1anaerobic.

%rotein metabolism is very intensive in kidneys. -s a result ammonia is formed from

glutamine and guanidineacetate from arginine and glycine. /hen guanidineacetate is

transformed in to creatine in the liver . /here are many enymes in the kidneys4

tissues :L=;, -s-/, -l-/. L=;#and L=;$dominate in the cortex and L= 9,7 in

the medulla.

M/'.+# $ *1#+/ $1,#$+

0luid , which contains different organic and non1organic substances, and is

eliminated from the organism is urine. Hrine contains: water, metabolic wastes,

mineral salts, hormones, vitamins, and their derivates, toxins.

;ow urine is formed

/here are 9 basic renal processes: filtration, reabsorption and secretion.

*lomerular !iltration is caused by difference between glomerular pressure (56 mm

;g), colloid oncotic pressure (96 mm ;g) and capsular pressure ($6 mm ;g).

/he effective filtration pressure is approximately 56mm;g 1 (96mm;g M

$6mm;g) N $6mm;g . &ncotic M capsular pressure must be lower than glomerular

pressure. -s a result of the filtration primary urine is formed. -ssuming that the

kidneys are healthy and filter approximately $6? of the plasma they receive each

minute, they will produce #@6 to $66 l of filtrate per day. /his fluid is essentially

protein1free and contains mostly crystalloids in theame concentrations as in the

plasma. -pproximately ? of the filtrate must be returned to the vascular system,

while #? is excreted in the urine. /he return flow of filtered molecules from the

tubules to the blood is called reabsor+tion. *ome substances are not being


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reabsorbedG such as: urea, uric acid, creatinine etc. /ubules reabsorb #5 l of water,

#kg of


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/he main portion of substances is reabsorbed by active transport which reBuires

the use of metabolic energy. /hat4s why system of active transport is very developed

in kidneys tubules. ;igh activity of !M-/%ase creates !Mgradient for

secondary active transport of different substances. -ll the substances are divided into

9 groups due to their extent of reabsorption in proximal tubules :

#.*ubstances which are actively reabsorbed

$.*ubstances which are reabsorbed not enough

9.*ubstances which are not reabsorbed

"ons of sodium, chloride, magnesium, calcium, water, glucose and other

monosaccharides, amino acids, phosphates, hydrocarbonates, proteins, etc are

actively reabsorbed.

lucose and proteins are reabsorbed approximately all, amino acids 1 up to 9?,

water 3 up to 2?,


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countercurrent system which takes part in concentration and dilutation of the urine

due to the normal range for the specific gravity of urine which is from #.66$ to #.696.

LiBuid, which is transferred from the proximal tubule to descending limb of the

loop of ;enle, passes in kidney one where concentration of osmoactive substances is

higher, than in cortex. /he walls of the ascending limb of the loop of ;enle are not

permeable to water. *alt (


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%rostaglandins influence for the elimination of water and


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permeability of the capillaries and dilatation of the vessels ,which leads to

decreasing of blood pressure

radykinin and collydin are examples of such kinins./hese peptides are formed

from kininogen (plasma globulin)under the influence of trypsin, plasmin etc..

(kallikreins).

R/+% 1/&*%,#$+ $ '#4 = / %+'/

/he kidneys help to regulate the blood p;, together with respiratory system and

the blood buffer systems. lood buffer systems very Buickly react to violation of p;

(in 6.71# min)G lungs influence on hydrogen ions concentration in #19 min G and

kidney is the latest regulator of p; (in #61$6 hours). /here are $ main mechanisms

which are responsible for the kidneys regulation of blood p;: reabsorption of sodium

and secretion of hydrogen ions.

#) +eabsorption of sodium ions during transformation the alkaline phosphate


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four hourUs diuresis can change depending on the kind of a diet, conditions of work,

the temperature of the environment and ets.

=rinking a lot of water causes the increase of diuresis to $66619666 ml, and

decrease of water drinking causes the decrease of diuresis to 566 ml and even less.

Consuming of fruits, berries and vegetables, rich in water also increase diuresis, but

dry products, especially salted, lower it. /he volume of urine is also lowered during a

work in hot shops when a man loses water mostly through sweating.

=iuresisUs increase (poliuria) is observed with many diseases and while using

different diuretics. - lot of urine is excreted by the patient who are ill with diabetes

mellitus and diabetes insipidus.

/wenty four hourUs decrease of urine excretion (oliguria) is observed while

having fever, diarhea, nausea, acute nephritis, heart deficieny and in some other

cases.

Ahen a man is lead or arsenic poisoned, is upset, has nephritis, the full stop of

urine excretion (anuria) is observed. %rolonged anuria causes uremia. -ccording to

standard, urine is discharged 918 times more by day 3 light time than at night. ut in

some pathological conditions (the beginning of heart decompensation, diabetes,

nephritis) become apparent by predominance of night discharge compare to day time.

*uch condition is called nicturia.

,rine-s colour. Hsually urine is straw 1yellow. "tUs main pigment is urochrome

which is formed from urobilin or urobilinogen during their interaction with some

peptides. *ome other pigments influence on the urineUs colour, thatUs uroerytryn which

is obviously derivate of melanin, uroporphyrins, riboflavin and others. =uring the

conservation obviously as a result of urobilinogen oxidation, urine darkens. *uch

urine is observed during bilirubinUsexcretion when a man is ill with obstructive or

hepatic Faundice.

Concentrated urine, which is excreted in large Buantities and has high specific

gravity, is of bright1yellow color.

%ale urine has low specific gravity and is excreted in large Buantities.


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Hrine can become of different colour shades when a patient has pathological

changes. Hrine is red or pink1red when a patient is ill with hematuria,

hemoglobinuria, when he takes amidopirin, santonin and other medicines. ;igh

concentration of urobilin and bilirubin can cause dark1red colour of urine.reen or

blue colour of urine is observed while albumin is rotting in the bowels and as a result,

indoxylsulphuric acids are produced. /he last ones while decomposing produce

indigo.

rans+arency. 0resh urine is transparent. sm 9which is

connected with periodical food and water intake and water output . 26127 grams of

hard substances are discharged with urine per day, specifically about $6 grams of

mineral left1overs. Hnder usually conditions an awerage level of urineUs density of

helthy person is #.6#$1#.6$6.

"ncrease of the density during a normal diuresis or poliuria is observed with that

patients who discharge a great amount of organic and nonorganic substanses. Hrine of


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the person with diabetes mellitus contains sugar, ketone bodies and other

substances, which cause not only poliuria, but a high density ( to #.697). =aily

diureses with low specific density of urine is observed among the patients with

diabetes insipidus. Hrine with low density which is similar to primary urine (#.6#6) is

constantly discharged when a person has a complicated form of renal failure. *uch

condition is called sthenuria, and it speaks about the disturbance of the

concentrational functions of kidneys.

Low density of urine which have patients with diabetes incipidus (#.66#1#.668)

is the result of the disturbance of reverseble reabsorption of water in kidneyUs

canaliculi becouse of lack of antidiuretic hormone.

&liguria which accompanies acute nephritis is characteried with high urineUs

density

,rine/s reaction.


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acute ammonia smell. ;ealthy peopleUs urine can have different smell, depending on

kind of meals. ;aving some garlic, horseradish, onion gives urine specific smell.

/aking medicines and also somediseases can give urine specific smell to.

O1&+#' '$$+/+, $ ,./ *1#+/

Proteins. ;ealthy man excretes about 96 mg of proteins with urine per day. /his

Buantity of the protein is not determined by ordinary lab. methods. -s a rule low

molecular proteins are eliminated , such as enymes( pepsin, trypsin , amilase,

ets.) , albumins. /he increasing of protein level in urine is called proteinuria.

/here are $ kinds of proteinuria: renal (real) and extrarenal (unreal or false).

+enal proteinuria is caused by organic demage of nephrons , due to blood proteins

(albumins and globulins) occur in urine. 0or example inflammation of glomeruluses

(glomerulonephritis )or nephrosis (violations of proteins reabsorption in tubules).

xtrarenal proteinuria1 availability of proteins in urine due to diseases of urinary

tract. (inflammation of urinary bladder, urethritis). %atients with such diseases may

loose $6 186 g of protein with urine per day .

,reais the main end1 product of the catabolism of amino acids and is the

substance in which is incorporated , for purposes of excretion, the bulk of the

nitrogen provided to the organism in excess of its needs.


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-n adult excretes about $19 g amino acids with urine per day. /wenty different

amino acids and their metabolites are determined in the urine. /he increasing of

amino acids concentration:

M#+/1% '$$+/+, $ ,./ *1#+/

"n normal conditions daily urine contains #7 to $7 g of mineral components.

*odium chloride is the most wide1spread non1organic substance in urine. "t is

excreted in amounts ranging from @ to #2 g per day by the kidneys.

-bout # kg of sodium chloride passes through the glomeruluses every day and

only # ? of this Buantity is eliminated from the organism.

"n normal conditions daily urine contains $ to 7 g of potassium. %otassium and

sodium are excreted paired with an anion (for example #l1).

#alcium and magnesium:

"n normal conditions daily urine contains 6,#16,9 g of calcium. xcreation calcium in

urine depends from its blood concentration. Ahen blood concentration of Ca is less

than @ mg ? calcium is not excreated in urine (for example hypoparathyroidism,

pregnancy).

"n normal conditions daily urine contains 6,6916,#@ g of magnesium.

*uch low #aandMgconcentration is because their salts are poorly soluble in

water.

0ron:

"n normal conditions daily urine contains about # mg of iron.

xcessive breakdown of erythrocytes in hemolytic types of anemia causes the

increasing iron concentration.

Pos+orus:

%hosphorus is excreted in urine as !;$%&8or


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Sul+ur:

*ulphur is excreted in the urine as sulphates and paired compounds. "n normal

conditions daily urine contains $19 g of sulphur.

Ammonia:

/he ammonia which is present in the urine is formed in the kidneys from amino

acids , such as glutamine and asparagine, for purpose of neutraliation of excreted

acid.

Vuantity of ammonia salts is eBual to 912? of total urinary nitrogen. Hrinary

ammonia is increased in many conditions associated with acidosis( diabetes mellitus,

starvation , dehydration, etc.)

R//1/+'/

#. Tohn A. *uttie. "ntroduction to iochemistry. 3


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Documents

Biochemistry of the Liver and Kidney. Urine Formation