Abstract
Serum glucose and immunoreactive insulin responses to an oral glucose load were measured before and several weeks after treatment with chlorpropamide in 18 patients with maturity-onset diabetes mellitus. The fall in serum glucose concentration produced by the sufonylurea compound was not associated with an increase in serum insulin concentration. Instead, there appeared to be a direct relationship between control of hyperglycemia and associated decreases in insulin concentration. These observations raised the possibility that sulfonylurea compounds may lower glucose concentration by means other than simply stimulating pancreatic insulin secretion.