4-Aminohippuric acid

Toxicity

The intravenous LD50 in female mice is 7.22 g/kg.

Description

4-Aminohippuric acid is a substrate for various renal transporters that has been used in the study of anion uptake in the kidney. It is a substrate for organic anion transporter 1 (OAT1; K_m = 14.3 μM in X. laevis oocytes), the human inorganic phosphate transporter (NPT1; K_m = 2.66 mM in HEK293 cells), and apical multidrug resistance protein (MDR2; K_m = 880 μM in HEK293 cells). 4-Aminohippuric acid is a glycine amide form of 4-aminobenzoic acid . Formulations containing 4-aminohippuric acid have been used as markers to determine renal plasma flow.

Chemical properties

off-white to greyish crystalline powder

The Uses of 4-Aminohippuric acid

4-Aminohippuric Acid is used in the measurement of renal plasma flow as a diagnostic tool which may be applied towards kidney disorders.

The Uses of 4-Aminohippuric acid

muscle relaxant (smooth)

The Uses of 4-Aminohippuric acid

p-Aminohippuric acid has been used as infusions to measure plasma flow.

Indications

Used to measure effective renal plasma flow (ERPF) and to determine the functional capacity of the tubular excretory mechanism.

Background

The glycine amide of 4-aminobenzoic acid. Its sodium salt is used as a diagnostic aid to measure effective renal plasma flow (ERPF) and excretory capacity. [PubChem]

Definition

ChEBI: P-aminohippuric acid is an N-acylglycine that is the 4-amino derivative of hippuric acid; used as a diagnostic agent in the measurement of renal plasma flow. It has a role as a Daphnia magna metabolite. It is a conjugate acid of a p-aminohippurate.

General Description

Renal tubules secretes para amino hippuric acid/PAH.

Biochem/physiol Actions

Para-aminohippuric acid(PAH) is used as a marker in nutrition studies to measure the flow of blood in pigs, which inturn helps to determine the portal-drained viscera (PDV) flux of nutrients.

Pharmacokinetics

Aminohippurate (p-aminohippuric acid, PAH, PAHA) is the glycine amide of p-aminobenzoic acid. It is filtered by the glomeruli and is actively secreted by the proximal tubules. At low plasma concentrations (1.0 to 2.0 mg/100 mL), an average of 90 percent of aminohippurate is cleared by the kidneys from the renal blood stream in a single circulation. It is ideally suited for measurement of ERPF since it has a high clearance, is essentially nontoxic at the plasma concentrations reached with recommended doses, and its analytical determination is relatively simple and accurate. Aminohippurate is also used to measure the functional capacity of the renal tubular secretory mechanism or transport maximum (TmPAH). This is accomplished by elevating the plasma concentration to levels (40-60 mg/100 mL) sufficient to saturate the maximal capacity of the tubular cells to secrete aminohippurate. Inulin clearance is generally measured during TmPAH determinations since glomerular filtration rate (GFR) must be known before calculations of secretory Tm measurements can be done.

Synthesis

4-Aminohippuric acid is prepared by reacting p-nitrobenzoyl chloride with glycine, followed by reducing the p-nitro group with tin and hydrochloric acid.

Metabolism

Not Available

Purification Methods

Crystallise the acid from H2O. It is soluble in organic solvents. [Cohen & McGilvery J Biol Chem 169 119 1945, 171 121 1947, Meunzen et al. J Biol Chem 26 469 1926, Beilstein 14 III 1069, 14 IV 1152.]

References

[1] B. ZMBOVA . Synthesis of p-aminohippuric acid analog and its labeling by technetium-99m[J]. International Journal of Radiation Applications and Instrumentation. Part A. Applied Radiation and Isotopes, 1989, 40 3: Pages 225-234. DOI:10.1016/0883-2889(89)90152-4.
[2] W P DEISS P P C. Studies in para-aminohippuric acid synthesis in the human: its application as a liver function test.[J]. Journal of Clinical Investigation, 1950, 29 8: 1014-1020. DOI:10.1172/JCI102332.
[3] M. SHEAT M. M Zenab F Saeed. Synthesis of Some of Azo, Triazines and Schiff Bases Compounds from 4-Aminohippuric Acid[J]. Journal of Education Science, 2009, 47 1: 1-8. DOI:10.33899/edusj.2009.57930.
[4] T SEKINE. Expression cloning and characterization of a novel multispecific organic anion transporter.[J]. The Journal of Biological Chemistry, 1997, 272 30: 18526-18529. DOI:10.1074/jbc.272.30.18526.
[5] HIROSHI UCHINO . p-Aminohippuric Acid Transport at Renal Apical Membrane Mediated by Human Inorganic Phosphate Transporter NPT1[J]. Biochemical and biophysical research communications, 2000, 270 1: Pages 254-259. DOI:10.1006/bbrc.2000.2407.