Glucose metabolism and β receptor function in atopic asthmatics

Abstract

Severe asthma and diabetes have been reported not to co-exist in the same patient. Various studies have attributed this to the possible association of asthma with hyperinsulinism, increased responsiveness to insulin or to beta-blockade. Previous studies have not addressed all these possible mechanisms in the same patient. In this prospective study, 7 atopic asthmatics and 7 age and sex-matched healthy controls underwent glucose, insulin and glucagon tolerance tests. The results showed no evidence of hyperinsulinism or increased responsiveness to insulin. Intravenous administration of glucagon, however, showed a lesser increase of glucose and insulin in asthmatics. Since glucagon has a gb-agonist effect on the liver and activates glycogenolysis and gluconeogenesis via β-receptor stimulation and stimulates insulin secretion by activating adenylate cyclase of pancreatic β-cells through β-receptors, the results of glucagon tolerance test in our study may therefore suggest the presence of partial beta-blockade in atopic asthmatics. asthma / beta-receptors / glucose metabolism.