For instance, PCLS were used to evaluate the functional role of VAP‐1, a hepatic amine oxidase, in promoting steatosis and inflammation.[132] Treatment of PCLS from healthy livers with recombinant VAP‐1 and its substrate methylamine led to increased lipid accumulation and reduced triglyceride secretion, suggesting that VAP‐1 promotes intracellular lipid retention. This evidence concerns the gene AOC3 and steatosis.