Figure 7. Characterization of tear endonuclease activity with inhibitors. Effects of endonuclease enzyme inhibitors: aurintricarboxylic acid (A), ZnCl₂ (B), G-actin (C) and NiCl₂ (D) on the activity of the minor endonuclease (■) and TL (▲).The standard deviations of all points varied between 10%–15%. Unlike other DNAses, the tear endonucleases are both sensitive to aurintricarboxylic acid and ZnCl₂, but a different concentrations. Neither was affected by G-actin. The activity of TL was not abrogated by NiCl₂. The minor endonuclease was only inhibited at a concentration of NiCl₂ greater than 1 mM.