Isoprenaline cannot act on pancreatic beta cells without hyperglycemia or alpha-block

Summary During long-term increase in isoprenaline (pronounced (β-effect) and isoprenaline plus regitine (pure β-effect) pancreatic insulin-secretion still depended mostly on blood glucose levels. This means that increased β-effect during normo- or hypoglycemia could not cause a higher insulin-secretion. Only during additional β-receptor blockade insulin-secretion was slightly but insufficiently increased. Catecholamines seem to be more regulator than originator of the insulin secretory process.