Fenoterol stimulates human erythropoietin production via activation of therenin angiotensin system

Aims The present study assessed the hypothesis that the Bz sympathomimetic fenoterol influences the production of erythropoietin (EPO) by activation o f the renin angiotensin system (RAS), i.e. angiotensin II. Methods In an open, parallel, randomized study healthy volunteers received i.v. either placebo (electrolyte solution), fenoterol or fenoterol in combi nation with an oral dose of the AT(1)-receptor antagonist losartan. Results Compared with placebo treatment AUC(EPO)(0,24 h) was significantly increased after fenoterol application by 48% whereas no increase in the gro up receiving fenoterol and losartan could be detected. The rise of PRA was statistically significant under fenoterol and fenoterol plus lorsartan. Conclusions Stimulation of EPO production during fenoterol infusion appears to be angiotensin II-mediated. Thus, angiotensin II may be considered as o ne important physiological modulator of EPO production in humans.