Abstract
The detailed effects of anti-insulin hormones in relation to insulin requirements have not yet been elucidated. The aim of the present study was to clarify the relationship between insulin requirements and diurnal changes of anti-insulin hormones. The patients comprised 18 diabetics in cluding 8 IDDM and 10 NIDDM. The blood glucose levels of the patients were normalized with an artificial endocrine pancreas (Biostator®) and blood samples were taken before each meal to measure the levels of plasma cortisol and serum growth hormone. Each meal was of identical size and composition (25-30 kcal/kg/day).
The results obtained were as follows.
(1) The insulin requirements after breakfast were significantly high (21±9 U) as compared to those after lunch (11±7U) and after supper (12±5 U)(p<0.01).
(2) The plasma cortisol levels before breakfast were significantly higher (137±40 ng/ml) than those before lunch (102±38 ng/ml, p<0.02) and before supper (81±38 ng/ml, p<0.001). However, in the case of the serum growth hormone levels, no significant differences were observed.
It was found therefore that the circadian rhythm of cortisol could affect the insulin requirements, indicating that much attention should be paid to the cortisol levels and caloric intake, especiallythe ratio of breakfast to total daily intake. We suggest that the percentage of insulin dosage in the morning should be raised when determining the insulin regimen.
