Cui Y, Lee T, Wang L C
Department of Zoology, University of Alberta, Edmonton, Canada.
Neurosci Lett. 1994 Jul 4;175(1-2):126-8. doi: 10.1016/0304-3940(94)91095-2.
Inclusion of the kappa agonist U50488 in the perifusion medium enhanced K(+)-stimulated 5-HT release from ground squirrel hippocampal slices, but reduced 5-HT outflow in both young and old rats' hippocampal slices. The stimulatory effect of U50488 on 5-HT release from ground squirrel hippocampus was not significantly attenuated by the non-specific opioid antagonist naloxone (10(-5) M), but was completely reversed by the specific kappa antagonist nor-BNI (10(-6)M), and the voltage-dependent sodium channel blocker TTX (10(-6)M). In contrast, the inhibitory effect of U50488 on 5-HT release from the young rat hippocampus was attenuated by naloxone (10(-6)M), but not by nor-BNI (10(-6)M) or TTX (10(-6)M). These results illustrate a significant species difference in the modulatory effect of opioids on neurotransmitter release in the hippocampus.
在灌流液中加入κ激动剂U50488可增强地松鼠海马切片中K⁺刺激的5-羟色胺释放，但降低了幼年和老年大鼠海马切片中的5-羟色胺流出量。U50488对地松鼠海马5-羟色胺释放的刺激作用未被非特异性阿片类拮抗剂纳洛酮（10⁻⁵ M）显著减弱，但被特异性κ拮抗剂nor-BNI（10⁻⁶ M）和电压依赖性钠通道阻滞剂TTX（10⁻⁶ M）完全逆转。相比之下，U50488对幼年大鼠海马5-羟色胺释放的抑制作用被纳洛酮（10⁻⁶ M）减弱，但未被nor-BNI（10⁻⁶ M）或TTX（10⁻⁶ M）减弱。这些结果表明阿片类药物对海马神经递质释放的调节作用存在显著的物种差异。
