Endogenous opiates do not influence glucose and lipid metabolism in rat adipocytes

The effects of the opiates beta-endorphin, dynorphin, met-enkephalin, leu-enkephalin, morphine and of the opiate-antagonist naloxone on glucose metabolism and lipolysis were studied in isolated rat adipocytes. None of the tested substances was found to alter 125I-Insulin binding. The opiates did not influence 2-deoxy-glucose uptake or glucose incorporation into lipids. They also did not exhibit a lipolytic activity. We conclude that the disturbances of glucose homeostasis induced by endogenous opiates are not mediated by an effect on peripheral glucose metabolism.