Abstract
1. In the glycogen formation the isolated diaphragm of normal rat showed better response than that of alloxan rat.
2. The glucose utilization and glycogen synthesis by normal and alloxan rat diaphragm were increased by the addition of insulin, where insulin 10-2 or 1 unit was added into the medium during the incubation.
3. The addition of mesoxalate alone or combined with insulin into the medium, no change in glucose utilization or glycogen synthesis was observed, while the diaphragm of the animal pretreated with mesoxalate showed increased responses on the glucose uptake in normal rats and the glycogen synthesis in alloxan rats.
4. The normal diaphragm produced marked amounts of glycogen by the previous injection of insulin or cortisone, but the similar treatment with ACTH or DOCA showed no change in glycogen formation. The addition of insulin into the medium caused decreased insulin effect with the previously cortisone treated rats, and for this case we may suggest the diaphragm by this treatment may become hyposensitive for added insulin.
5. The addition of insulin into the medium, in the case of pretreatment of mesoxalate or ACTH to the normal or alloxan animals, and in the case of cortisone injected alloxan diaphragm, the insulin effect both on the glucose uptake and glycogen synthesis were increased.
6. It is of interest that the alloxan diaphragm with all the cases of pretreatment of mesoxalate and pituitary adrenal cortical hormones showed increased insulin effect both on the glucose uptake and glycogen formation by adding insulin into the medium.
From these findings, it would be suggested that in the alloxan diaphragm the endocrine balance is altered, and there is some factor, which makes the tissue hypersensitive to insulin.
