“ Lactase specific activity in brush border membranes was decreased by 26%-27% during incubation with trypsin at pH 7.0 in patients with normal intestinal lactase levels, whereas in patients with lactase deficiency the inactivation was 75%.”
“Therefore, in these patients the greater in vitro lactase inactivation by trypsin could be explained at least in part by an increased trypsin/lactase ratio.”