Adaptation of the Quick – Pytel test protocol for the assessment of liver antitoxic function in mice

Introduction. Functional liver tests are a relevant group of methods for liver function screening, that can be used in a laboratory setting as well as in clinical practice. This group includes, among others, the Quick – Pytel test, which is based on the enzymatic formation of hippuric acid from glycine and benzoate in the liver. This test is minimally invasive and comparatively ease to perform, yet as of now, there is no detailed protocol to carry it out in small laboratory animals.

Aim. The objective of this work was to develop a protocol of the Quick – Pytel test to assess liver antitoxic function in small laboratory animals.

Materials and methods. Loading doses of sodium benzoate and glycine at an equimolar ratio (504 mg/kg and 264 mg/kg, respectively) were administered intraperitoneally to white outbred male mice (n = 10), after which urine samples were collected over 18 h in metabolic cages. Following sample preparation, the newly formed hippuric acid was titrated by 0.01 N potassium hydroxide in the presence of 1 % phenolphthalein. In 1 week, the mice were injected with carbon tetrachloride (1 mL/kg) to induce acute toxic hepatitis, and the test was repeated. Liver injury was confirmed morphologically with haematoxylin and eosin staining.

Results and discussion. Following carbon tetrachloride administration, urinary concentrations of hippuric acid decreased significantly (p < 0.01) by over 50 % from baseline. Liver samples exhibited characteristic features of acute toxic hepatitis.

Сonclusion. We have developed a protocol of the Quick – Pytel test in mice and confirmed its applicability to assess liver antitoxic function under acute injury conditions. The method we describe is simple and straightforward, is relatively low-cost, and can be used in routine practice to assess liver function in small laboratory animals.

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