REPRODUCIBILITY AND CONSISTENCY OF THE RESPONSES TO SUPINE BICYCLE ERGOMETRY - EVALUATION IN CONJUNCTION WITH BETA(1)-ADRENOCEPTOR OCCUPANCIES

A protocol is presented for supine bicycle ergometry in healthy subjec ts, which aims for a target increase of heart rate (HR = 140 beats min (-1)) after 4 min cycling under constant load. The required load is se lected from a pre-study ergometry with stepwise increasing load. Repea ted testing with this protocol was shown to yield highly reproducible ergometric HR-responses. Because of their high reliability, the ergome tric endpoints and increments permit a highly sensitive comparison of beta 1-adrenoceptor antagonism across dose and time within a given com pound. The relationship between the changes of the ergometric rise of HR and the beta 1-adrenoceptor occupancy (estimated from radioreceptor assay data) permits to evaluate the ergometric efficiency of differen t beta-adrenoceptor antagonists across time and doses and to identify eventual differences that do not relate primarily to the extent of bet a 1-adrenoceptor antagonism itself.