Steinfels G F, Cook L
Peptides. 1985;6 Suppl 2:171-5. doi: 10.1016/0196-9781(85)90151-2.
The analgesic activity of the prototypic opioid peptides for the mu (D-Ala2-Me-Phen4-Gly-ol5-enkephalin [DAGO]) kappa (Dynorphin 1-13), delta (D-Ala2-D-Leu5-enkephalin [DADLE]), or epsilon (beta-endorphin) receptor was assessed in a rat tooth pulp stimulation procedure. All opioid peptides tested and the opioid alkaloid U50, 488H (kappa receptor agonist) significantly elevated response thresholds. The rank order of potency based on the Minimum Effective Dose values was beta-endorphin greater than DAGO = dynorphin A (1-13) amide greater than DADLE greater than dynorphin A (1-13) greater than U50,488H. Based on absolute magnitude, the rank order of dose response slopes was DAGO greater than U50,488H greater than dynorphin A (1-13) amide greater than beta-endorphin greater than DADLE. Dynorphin A (1-13) produced the shallowest dose response slope and the magnitude of response threshold was the lowest for all compounds tested. Finally, the general conclusion that mu agonists are effective against noxious stimuli derived from thermal, chemical, and mechanical is extended by our data to include electrical sources derived from tooth pulp stimulation; kappa agonists are effective against noxious stimuli derived from chemical, mechanical, and electrical sources (tooth pulp stimulation) and delta agonists are effective analgesics against thermal, chemical and electrical stimuli (tooth pulp stimulation).
在大鼠牙髓刺激实验中评估了原型阿片肽对μ（D-丙氨酸2-甲基苯丙氨酸4-甘醇5-脑啡肽[DAGO]）、κ（强啡肽1-13）、δ（D-丙氨酸2-D-亮氨酸5-脑啡肽[DADLE]）或ε（β-内啡肽）受体的镇痛活性。所有测试的阿片肽和阿片生物碱U50,488H（κ受体激动剂）均显著提高了反应阈值。基于最小有效剂量值的效价顺序为β-内啡肽>DAGO =强啡肽A（1-13）酰胺>DADLE>强啡肽A（1-13）>U50,488H。基于绝对幅度，剂量反应斜率的顺序为DAGO>U50,488H>强啡肽A（1-13）酰胺>β-内啡肽>DADLE。强啡肽A（1-13）产生的剂量反应斜率最浅，且在所测试的所有化合物中反应阈值幅度最低。最后，我们的数据扩展了关于μ激动剂对源自热、化学和机械的有害刺激有效的一般结论，使其包括源自牙髓刺激的电刺激；κ激动剂对源自化学、机械和电刺激（牙髓刺激）的有害刺激有效，而δ激动剂对热、化学和电刺激（牙髓刺激）是有效的镇痛药。
