The experimental coronary insufficiency was produced in normal dogs. The coronary sinus catheterization showed remarkable decrease in thiamine uptake-ratio of myocardium, and thiamine, especially the esterified form, of myocardium remarkably decreased compared with control. The anoxic state was made on rats with the use of N_2 gas, and the marked reduction of thiamine, especially the esterified form, of heart muscle was observed in comparison with normal control.