Comparison of renal and cardiac lymph constitutents

The concentration of various substances were measured in renal and cardiac lymph and arterial and venous plasma to determine if lymph constituents might indicate events occurring at the cellular level in these two organs. The study utilized anesthetized dogs. Magnesium, calcium, pyruvate and glucose concentrations were similar in the four fluids. Cardiac lymph contained significantly higher concentrations of creatine phosphokinase, lactic dehydrogenase and lactate. Renal lymph contained lower concentrations of zinc and protein while both renal and cardiac lymph contained less copper than arterial plasma. Venous plasma contained more copper than the other fluids. It is concluded that lymph composition reflects events occurring in the cells, especially for substances that are not readily diffusable through blood capillary endothelium.