Uroerythrin is a red pigment present in the

urine Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (mal ...

, where it is part of a group of yellow, brown and red pigments generally designated as ''urochrome''.

Urinary pigments

Pigments excreted in urine are partially absorbed by

urate Uric acid is a heterocyclic compound of carbon, nitrogen, oxygen, and hydrogen with the formula C5H4N4O3. It forms ions and salts known as urates and acid urates, such as ammonium acid urate. Uric acid is a product of the metabolic breakdown of ...

sediments ('' sedimentum lateritium ''), which consists of cell debris and sedimented urinary components formed when the acidified urine is stored below room temperature. These urate sediments looks reddish or pink due to the presence of a main pigment first introduced by Simons in 1842 as uroerythrin,

Clinical significance

From early clinical observations it is known that uroerythrin is present in every urine and increased amounts are observed in pathological states, ''e.g.'' metabolic disorders with high fever or tissue degradation.

Chemical structure

The chemical structure of most of urochromes is still unknown, since they are very labile pigments that are easily decomposed in the light. In particular uroerythrin, remains unresolved until 1975 with previous papers that describes it like a peptidic compound.Hansen, S. E. (1969) ''Acta Chenz. Scand.'' 23, 3466-3472 In 1975 its structure was described based on

mass spectrometry Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used ...

infrared spectroscopy Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functio ...

and

nuclear magnetic resonance Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong constant magnetic field are disturbed by a weak oscillating magnetic field (in the near field) and respond by producing an electromagnetic signal with a ...

References

{{reflist Urine Pyrroles