Fig. 2.

Dromyosuppressin (DMS)-induced changes on the cardiac activity of the blowfly. Electrocardiogram (ECG) was continuously recorded before, during, and after injection of 0.5 μl of a 0.1 ηM DMS solution. Before injection, the fast phase and the slow phase alternated regularly in a cardiac cycle (first line). A few seconds after injection (arrow), there was no signal (second line; continuous recording from first line, see arrowheads). A recovery of alternating fast phase and slow phase occurred after 2 minutes (third line). However, signal frequency was reduced compared to before injection even 10 minutes later (end of the fifth line).