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Updated: Jun 10, 2026

Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase
Published on: November 23, 2016
Influence of prior freezing on arylamine acetylation by human liver preparations
C E Green1, G R Gordon, J H Peters
1SRI International, 333 Ravenswood Avenue, Menlo Park, CA 94025, USA.
Abstract:
Human liver tissue is an important resource for use in xenobiotic metabolism studies. Because of the scarcity of human livers, studies are frequently conducted with subcellular preparations from previously frozen material. The influence of prior freezing on arylamine acetylation with human S-9 was studied and differences were found between S-9 preparations derived from fresh liver and from stored frozen liver. Specifically, the capacity for formation of diacetylated benzidine was lost as a result of tissue freezing, and the rate and extent of monoacetylation appeared to be reduced also, though not as dramatically. These results demonstrate that freezing of human tissue prior to conducting metabolism studies with arylamines may alter metabolite profiles and indicate that, for reliable data, before using frozen human tissue in metabolism studies with arylamines one should check first for this possibility.
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