caa a22 4500 477057306 CHVBK 20180405111350.0 cr unu---uuuuu 170330e19960601xx s 000 0 eng 10.1007/s002280050119 doi (NATIONALLICENCE)springer-10.1007/s002280050119 Exercise increases plasma concentrations of (R)- and (S)-propranolol [Elektronische Daten] [K. Stoschitzky, M. Schumacher, G. Stark, H.-P. Dimai, R. Stauber, P. Stoschitzky, G. J. Krejs, W. Klein, W. Lindner] Objective: We recently reported a highly stereoselective increase in plasma concentrations of (S)-atenolol during exercise which is most likely due to a release of the drug from adrenergic cells. The objective of the present study was to investigate the influence of physical exercise on plasma concentrations of the (R)- and (S)-enantiomers of propranolol. Methods: Blood samples were taken immediately before and at the end of exercise in 12 patients receiving chronic treatment with racemic (R, S)-propranolol. Plasma concentrations of (R)- and (S)-propranolol were determined by HPLC. Results: In contrast to atenolol, mean plasma concentrations of (S)-propranolol were significantly higher (+20%) than those of (R)-propranolol at rest. During exercise there was an increase in plasma concentrations of both (R)-propranolol (+129%) and (S)-propranolol (+109%). Conclusion: Based on information from in vitro studies we conclude that the increase in plasma concentrations of (S)-propranolol during exercise is caused by a release of the drug from adrenergic nerves, whereas the reason for the increase in (R)-propranolol remains to be determined. This release of the β-adrenoceptor blocking (S)-enantiomer directly at the synaptic gaps might be one reason for the poor correlation between plasma concentration and effect of β-adrenoceptor antagonists repeatedly described in the literature. Springer-Verlag Berlin Heidelberg, 1996 Key words Propranolol nationallicence stereoselectivity nationallicence chirality nationallicence enantiomers nationallicence isomers nationallicence Stoschitzky K. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut Schumacher M. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut Stark G. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut Dimai H.-P Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut Stauber R. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut Stoschitzky P. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut Krejs G. J. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut Klein W. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut Lindner W. Institute of Pharmaceutical Chemistry, Karl Franzens University, Graz, Austria, AT aut https://doi.org/10.1007/s002280050119 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s002280050119 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Stoschitzky K. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut NATIONALLICENCE 700 1- Schumacher M. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut NATIONALLICENCE 700 1- Stark G. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut NATIONALLICENCE 700 1- Dimai H.-P Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut NATIONALLICENCE 700 1- Stauber R. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut NATIONALLICENCE 700 1- Stoschitzky P. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut NATIONALLICENCE 700 1- Krejs G. J. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut NATIONALLICENCE 700 1- Klein W. Department of Medicine, Karl Franzens University, Auenbruggerplatz 15, A-8036 Graz, Austria, AT aut NATIONALLICENCE 700 1- Lindner W. Institute of Pharmaceutical Chemistry, Karl Franzens University, Graz, Austria, AT aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer