抄録
The carbohydrate and lipid metabolism along with the effects of epinephrine, insulin and hydrocortisone on it were investigated in rat heart slices using C14-labeled glucose and palmitate-l-C14, in order to clarify the mode of action of such hormones on the myocardial metabolism as well as to verify the existence and the role of the oxidative pentose pathway. The results obtained were as follows:
(1) Epinephrine depressed the oxygen consumption, the oxidative pentose pathway and the oxidation of palmitate-l-C14. However, the Embden-Meyerhof pathway was hardly affected by epinephrine.
(2) Insulin facilitated the oxygen consumption and the glucose metabolism, but the Embden-Meyerhof pathway was stimulated more than the oxidative pentose pathway by the addition of insulin. On the other hand, the oxidation of palmitate-l-C14 was depressed by insulin.
(3) Hydrocortisone did not show any uniform effects on the carbo-hydrate metabolism of the resting normal rat heart muscle, however, the oxidation of palmitate-l-C14 was suppressed by the addition of hydrocortisone.
(4) Palmitate-l-C14 was utilized by the heart muscle for fuel as well as carbohydrates.
(5) The heart muscle was again confirmed, by means of the addition of hormones, to catabolize glucose via both the Embden-Meyerhof pathway and the oxidative pentose pathway.
(6) Comparing the effects of hormones on the metabolism of the normal rat heart slices with those of other organs or tissues, the peculiarity of the heart muscle was briefly discussed.
