Effects of noncatechol sympathomimetics on glucose output by hepatocytes from normal and dexamethasone-treated rats.

Isolated hepatocytes from collagenase-perfused rat livers were used to study the hyperglycemic potential of various noncatechol sympathomimetics (NCSPM) commonly found in commercially available cough/cold preparations. The effect of various concentrations of ephedrine, pseudoephedrine, and phenylpropanolamine on glucose output were compared in dexamethasone- or saline-pretreated rats. The NCSPM produced minimal or no glucose output at most of the concentrations tested in hepatocytes from normal saline pretreated rats. However, these same compounds were able to stimulate a significant increase in glucose output from hepatocytes pretreated with dexamethasone. The results indicate that corticosteroids can enhance the glycemic potential of characteristically weak, indirectly acting NCSPM.