Increased Molar Proinsulin-to-Insulin Ratio in Women With Previous Gestational Diabetes Does Not Predict Later Impairment of Glucose Tolerance

Abstract
Objective To evaluate the catecholamine response during human and pork insulin-induced hypoglycemia. Research Design and Methods Ten insulin-dependent diabetes mellitus (IDDM) patients without any signs of autonomic neuropathy received either human or pork insulin in a randomized crossover fashion on 2 nonconsecutive days. The glucose clamp technique was applied to achieve stable glycemic plateaus of 5.6, 3.3, 2.2, and 1.7 mM. Results The effect of both types of insulin on glucose metabolism and circulating catecholamines was almost identical. There was a sharp rise of both epinephrine (P < 0.05) and norepinephrine (P < 0.02) during hypoglycemia,which did not depend on the type of insulin applicated. Symptom awareness increased significantly during the decrease of blood glucose concentration. Only during developing hypoglycemia (3.3-mM plateau), was this effect more pronounced (cumulative symptom score 2 vs. 26, P < 0.05) with pork insulin. Conclusions An attenuated catecholamine secretion seems not to be the putative mechanism of a reduced awareness of human insulin-induced hypoglycemia.