Studied was the dynamics of the changes taking place in the activity of a number of enzymes in the blood plasma (glutamate oxalacetate transaminase (GOT), glutamate pyruvate transaminase (GPT), lactate dehydrogenase (LDH), alkaline phosphatase (AP), aldolase (ALD), creatine phosphokinase (CPK), guanase, and cholinesterase (CE). The calculation of the correlation coefficients and the regression lines revealed that GOT, GPT, LDH, ALD, and guanase raised their activity following treatment of the test animals up to a higher extent and at a higher rate. Lower rate changes were those in the activity of AP, leucinaminopeptidase, and CE. No changes whatever were found in the activity of CPK. On the basis of these results the diagnostic value is determined of both the individual enzymes and the enzyme constellation as a whole.