INFLUENCE OF CONTINUOUS PERFUSION WITH ADRENALINE ON THE WORKING RAT-HEART

In this study, the effect of perfusion with increasing adrenaline concentrations on the performance of the working rat heart was continuously monitored. The results showed that adrenaline increased the rate of heart beat ar a faster pace than the mechanical parameters. When the maximum heart-beat rate was reached, this value was maintained, whereas the mechanical function started to decline soon after a plateau in performance was attained. Increasing the adrenaline concentration caused the inotropic function to respond up to a plateau value and then to decline. Adenosine production increased at the time of decline in mechanical performance. This increase in adenosine levels might be one of the factors causing the suppression of contractility, possibly by inhibition of kinase activity.