Креатинин

Описание

Creatinine is together with urea, the most widely known "uremic toxin", and is usually assessed when- ever a reduction in kidney function is suspected. This is mainly because creatinine evaluation is cheap, widely accessible and relatively well reflects the renal function. It also forms the basis for estimation of estimated glomerular filtration rate (eGFR) and thus is a major component of all principal eGFR equations.
Creatinine, which is nonenzymatically produced from the creatine pool in skeletal muscle, but is also to some extent generated from exogenous creatine present in meat, is the major guanidine compound retained in patients with diminished glomerular filtration rate. Creatinine is routinely determined in plasma or serum as a measure of impairment of renal function and it might be expected that a variety of uremic symptoms correlate with the plasma creatinine level; this does not, however, necessarily imply a causal relationship. In fact, high serum creatinine levels correlate with low mortality in HD patients, presumably because the creatinine generation rate reflects the size of the muscle mass. Creatinine seems to be relatively nontoxic. Large amounts of creatinine have been fed to healthy subjects without any adverse effects and animals also tolerate large doses.

Химические свойства

white powder

Использование

Creatinine is the end product of creatine catabolism. Creatinine is a normal constituent of urine. Also found together with creatine in muscle tissues and blood. Creatinine is found in all soils and i n grain seeds and other vegetable matter as well as in certain fish and in crab meat extract.

Определение

ChEBI: A lactam obtained by formal cyclocondensation of creatine. It is a metabolite of creatine.

Биологические функции

Creatinine is a byproduct of a chemical compound called creatine, which helps muscles get the energy that they need. As a waste product, creatinine is filtered out of the blood by the kidneys and removed from the body in urine.
A creatinine test measures the amount of this chemical in either the blood or urine. Creatinine levels can provide an indication of how well the kidneys are working.
Creatinine may be measured alone or included in a panel of tests that include other compounds found in the urine or blood.
https://labtestsonline.org/tests/creatinine
https://www.kidney.org/atoz/content/what-creatinine

Общее описание

Creatinine is a breakdown product formed by the degradation of creatine phosphate from muscles. The kidneys extract creatinine from the body by filtering almost all of it from the blood and excreting it in the urine. Serum creatinine is the most commonly used indicator for renal functioning. In chemical synthesis, creatinine is used as a heterocyclic nitrogenous compound that produces electron-rich and highly basic creatinine derivatives.

Методы очистки

Likely impurities are creatine and ammonium chloride. Dissolve it in dilute HCl, then neutralise with ammonia. Recrystallise it from H2O by adding excess of Me2CO. The picrate crystallises from 23volumes of boiling H2O and has m 220-221o(dec). [King J Chem Soc 2377 1930, Beilstein 25 III/IV 2543.]