If the liver of a healthy animal is removed under aseptic precautions and so preserved as to exclude bacterial action, it will be found that after a considerable time, from a few weeks to a few months, the tissue softens and disintegrates. Examination of the residue snows that it contains in large amounts substances that are associated with the results of digestive processes, such as leucin and tyrosin, in earlier stages albumoses. Attention was first directed to this phenomenon of self-digestion, or autolysis, by Salkowski. As will be observed the products of digestion are analogous to those obtained by trypsin digestion, as characterized by leucin and tyrosin, rather than those resulting from pepsin action. Other observers, however, have shown that this latter ferment is present in the tissues normally, notably in muscles, but under ordinary circumstances the alkalinity of the tissues prevents the pepsin from producing any changes.
SELF-DIGESTION OF TISSUES.. JAMA. 1901;XXXVII(23):1536. doi:10.1001/jama.1901.02470490034003