Hernández L L, Singha A K
William Jennings Bryan Dorn Veterans Affairs Medical Center, Columbia, South Carolina 29209-1639, USA.
Exp Clin Psychopharmacol. 1998 Feb;6(1):10-21. doi: 10.1037//1064-1297.6.1.10.
The nonpeptide delta-opioid agonist BW373U86 (3 to 300 micrograms/kg) was tested in rabbits for effects on heart rate, cardiac orienting and Pavlovian conditioned responses to tones, and unconditioned cardiac and somatomotor responses to signaled and unsignaled shocks. BW373U86 did not alter shock-evoked somatomotor reflexes and had few effects on the development or retention of Pavlovian conditioned heart rate discrimination. However, BW373U86 appeared to modulate cardiac conditioning indirectly, by facilitating sympathetic reflexes evoked by the signaled stressor, and the dose effect was U-shaped within the dose range tested. The pronounced tachycardiac effect of BW373U86 was completely blocked, or rapidly reversed, by the selective delta-opiate antagonist naltrindole. BW373U86 was more potent in increasing signaled than unsignaled shock-evoked tachycardia, suggesting release of an endogenous substance (e.g., a delta-opioid) because of the Pavlovian conditioning contingency.
非肽类δ-阿片受体激动剂BW373U86（3至300微克/千克）在兔子身上进行了测试，观察其对心率、心脏定向以及对音调的巴甫洛夫条件反应的影响，还有对有信号和无信号电击的非条件心脏和躯体运动反应的影响。BW373U86并未改变电击诱发的躯体运动反射，对巴甫洛夫条件性心率辨别能力的形成或保持影响甚微。然而，BW373U86似乎通过促进由有信号应激源诱发的交感反射间接调节心脏条件反射，并且在所测试的剂量范围内剂量效应呈U形。BW373U86明显的心动过速效应被选择性δ-阿片受体拮抗剂纳曲吲哚完全阻断或迅速逆转。BW373U86在增加有信号电击诱发的心动过速方面比无信号电击更有效，这表明由于巴甫洛夫条件性意外事件释放了一种内源性物质（例如，一种δ-阿片类物质）。
