Effects of sumatriptan on isolated rabbit heart.

Sumatriptan provokes, in healthy subjects as well as in those who suffer from hemicrania, a slight increase in both systolic and diastolic arterial pressure. It has also been shown to increase the pressure of pulmonary circulation and to reduce the calibre of coronary arteries. The present investigation was undertaken to study the effects of sumatriptan (75 ng/l) on isolated rabbit hearts. Fifteen isolated rabbit hearts, perfused according to Langerdoff's procedure, were divided into two groups: Group I (5 hearts), perfused with Krebs-Henseleit solution, as a control, and Group II (10 hearts), perfused with Krebs-Henseleit mixed with sumatriptan succinate (75 ng/l). After 30 min of perfusion, the basal values of heart rate (HR) dp/dt, systolic ventricular pressure (SVP), diastolic ventricular pressure (DVP) and coronary flow (CF) were measured. The above values in either control or treated hearts were measured 5, 15, 30, 45, 60 min after recording the baseline values. HR, SVP, DVP, dp/dt and CF did not show significant differences in the two groups. The present data suggest that sumatriptan does not exert any action on isolated rabbit hearts.