Kalivas P W, Richardson-Carlson R, Duffy P
J Pharmacol Exp Ther. 1986 Sep;238(3):1126-31.
Neuromedin N (NN) is a hexapeptide recently isolated from porcine spinal cord that shares a four-amino acid homology with the C-terminus of the biologically active tridecapeptide neurotensin (NT). Microinjection with NT into the ventral tegmental area or nucleus accumbens of rats has been shown to increase locomotor activity and dopamine (DA) metabolism in some limbic areas or to inhibit the motor stimulant effect of intra-accumbens administration of DA, respectively. In this study the effects of microinjected NN were compared with those of NT. After injection into the ventral tegmental area, NN was shown to be more potent than NT at increasing spontaneous motor activity and to produce an increase in DA metabolism in the nucleus accumbens, prefrontal cortex, diagonal band of Broca and septum. However, when injected into the nucleus accumbens, NN was markedly less potent than NT at inhibiting DA-induced behavioral hyperactivity. In addition to DA-related effects, i.c.v. injection with NT causes hypothermia, and i.c.v. administration with NN was without effect on colonic temperature. These data demonstrate that NN has a behavioral profile distinct from that of NT.
神经介素N（NN）是一种最近从猪脊髓中分离出的六肽，它与具有生物活性的十三肽神经降压素（NT）的C末端有四个氨基酸的同源性。已表明，向大鼠腹侧被盖区或伏隔核微量注射NT可分别增加某些边缘区域的运动活性和多巴胺（DA）代谢，或抑制伏隔核内注射DA的运动兴奋作用。在本研究中，将微量注射NN的效果与NT的效果进行了比较。注射到腹侧被盖区后，NN在增加自发运动活性方面比NT更有效，并使伏隔核、前额叶皮质、布罗卡斜带和隔区的DA代谢增加。然而，当注射到伏隔核中时，NN在抑制DA诱导的行为多动方面明显不如NT有效。除了与DA相关的作用外，脑室内注射NT会导致体温过低，而脑室内注射NN对结肠温度没有影响。这些数据表明，NN具有与NT不同的行为特征。
