Effects of methoxyadiantifoline on the physiologic properties of rat atria

Methoxyadiantifoline (MAF) is a new alkaloid isolated from Thalictrum ome iense W.T. Wang. Its effects upon the physiologic properties of myocardium were studied on isolated rat left and right atria muscle. 40 minutes after MAF 30 μM was added, the contractility of left atria was decreased: to 50±9%. 15 minutes after the addition of MAF 30 μM, the functional refractory period (FRP) was prolonged from 61±2 ms to 90±3.0 ms while the epinephrine concentration needed to induce automaticity was increased from 14±7 μM to 42±9μM. The MAF concentration shifting the duration-intensity curve to the right was 50 μM. The contractility and frequency of rat right atria muscles were decreased to 50 % and 60 % respectively.