Liver aspartate aminotransferase activity as a power function of body weight.

Total liver enzyme activity (E) for aspartate aminotransferase (ASAT; EC 2.6.1.1) per gram body weight (W) decreases in six species as body weight increases from mice to cattle according to the equation E/W 0.85 = c, where c is a constant. The 0.85 power of body weight thereby provides a reference standard for the direct arithmetic comparison of liver ASAT activities in six species with different body weights. The use of W 0.85 should provide a tool in clinical studies in which data from experimental animals must be related to humans, e.g., in establishing the relationship between drug dosage (or toxicity) and body weight.