Secretin: high plasma levels in diabetes mellitus

Plasma immunoreactive secretin levels were measured in 22 newly diagnosed non-ketotic, maturity-onset diabetics and 10 healthy control subjects during 50 gram oral glucose tolerance test (OGTT). The test was repeated in the diabetic group after 6 months' dietary treatment. At diagnosis the fasting secretin levels in the diabetics were higher than in control subjects but fell within the normal range following dietary treatment. In the diabetics there was a significant positive correlation between the fasting glucose and fasting secretin levels at the time of diagnosis. Suppression of secretin levels occurred during the OGTT, both in diabetic and control subjects.