[Age dependence of increase in heart rate after vagolysis (author's transl)]

Age dependent decrease of heart rate in sinus rhythm at rest was shown under clinical and experimental conditions and correlated with a decrease of sympathetic storage granula and membranes indicated by the tissue concentrations of c-AMP, which can be regarded as a messenger at the receptor sites. A slower maximal heart rate after Atropine and a reduced increase during oral medication with Ipratropium bromide can be explained by a reduced cardiac sympathetic threshold. The mentioned age dependent differences of the sympathetic stimulation can not be deduced to myocardial changes, because CPK and CK-MB activities were similar in the different age groups.