[ANALGESIC EFFECT OF TROPALGIN ON THERMAL PAIN IN RATS WITH DIFFERENT PAIN THRESHOLDS].

Experiments on rats divided into two groups (with high and low pain sensitivity) were used to assess the effect of tropalgin, a new derivative of tropine, in thermal pain tests (tail-flick and hot plate). Tropalgin was found to possess an analgesic effect comparable to that of reference sodium metamizole. ED50 of tropalgin was 2 mg/kg for intraperitoneal administration. The duration of the analgesic effect of tropalgin in rats low pain sensitivity was longer than in animals highly sensitive to pain. It is suggested that the analgesic effect of tropalgin can be related to the adenosine liberating action of this drug.