A generalized increase in tissue cAMP concentrations after an i.v. injection of cholera enterotoxin may play a role in the development of biochemical and pathological changes leading to death. Dutch rabbits were injected i.v. with highly purified cholera enterotoxin at a dose of 100 or 200 .mu.g/kg. When death appeared imminent (20-30 h after inoculation), rabbits were anesthetized; plasma, urine and 13 different tissue samples were obtained for cAMP determinations. Enterotoxin (200 .mu.g/kg) produced significant increases in cAMP concentrations in lung, spinal cord, skeletal muscle, renal cortex, renal medulla and liver, whereas a lower dose (100 .mu.g/kg) had no effect on cAMP levels in any tissue. The elevation of cAMP values in selected tissues suggests differences in tissue sensitivity to cholera enterotoxin; the data fail to support in toto the proposed hypothesis.