The effect of the tetrapeptide H-Tyr-D-Arg-Phe-Gly-NH₂ (Taphalgin), a synthetic derivative of dermorphine, was evaluated in the tail-flick test in mice after a single subcutaneous (s.c.) injection. Taphalgin significantly prolongs the tail-flick latency when administered in the dose range 0.01 – 5 mg/kg. The analgesic effect of a single s.c. injection of Taphalgin at 1 mg/kg exceeds the effect of morphine hydrochloride at the same dose. The effect of Taphalgin at 0.5 mg/kg is comparable to that of morphine hydrochloride at 1 mg/kg. The magnitude and duration of the analgesic effect grow as the dose of Taphalgin increases from 0.5 to 1.5 and 4.5 mg/kg. The maximum 4-h duration of the analgesic effect is observed at doses of 1.5 and 4.5 mg/kg.

四肽 H-Tyr- D -Arg -Phe-Gly-NH ₂ (Taphalgin)（一种皮吗啡的合成衍生物）的作用在小鼠单次皮下 (sc) 注射后的甩尾试验中进行了评估。当在 0.01 – 5 mg/kg 的剂量范围内给药时，Taphalgin 会显着延长甩尾潜伏期。单次皮下注射 1 mg/kg Taphalgin 的镇痛效果超过相同剂量的盐酸吗啡。0.5 mg/kg 的 Taphalgin 的作用与 1 mg/kg 的盐酸吗啡相当。随着 Taphalgin 的剂量从 0.5 增加到 1.5 和 4.5 mg/kg，镇痛作用的强度和持续时间增加。在 1.5 和 4.5 mg/kg 的剂量下观察到最长 4 小时的镇痛作用持续时间。