Level of Total Proteolytic Activity in Rat Intestinal Lymph, Lymph Nodes, and Lymphocytes

The level of total proteolytic activity in different parts of the lymphatic system of the rat intestine was examined to clarify the possible involvement of the lymphatic system in the degradation of transported proteins, especially denatured ones. The levels of total proteolytic activity in the lymph nodes and mesenteric lymph were 512.12±27.84μgGly/g×hour and 40.98±3.42μgGly/ml×hour, respectively. We calculated that the level of activity of proteases embedded into the lymphocyte plasma membranes was approximately 3.51±0.37μgGly per 10^6 of cells per hour. We also found that the lymphatic vessel wall itself not only participates in the proteolysis process but also modulates this process which is being carried out by other parts of the lymphatic system. The protein denaturation increases the total activity of proteolytic enzymes in lymph and lymph nodes by 37.16% and 124.62%, respectively. These data suggest that all parts of the lymphatic system investigated participate in the change of protein content during its transportation by lymph.