PT  - JOURNAL ARTICLE
AU  - P W Kalivas
AU  - R Richardson-Carlson
AU  - P Duffy
TI  - Neuromedin N mimics the actions of neurotensin in the ventral tegmental area but not in the nucleus accumbens.
DP  - 1986 Sep 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 1126--1131
VI  - 238
IP  - 3
4099  - http://jpet.aspetjournals.org/content/238/3/1126.short
4100  - http://jpet.aspetjournals.org/content/238/3/1126.full
SO  - J Pharmacol Exp Ther1986 Sep 01; 238
AB  - 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.