Cocaine has some effect on neuromedin U expressing neurons related to the brain reward system

• Published in: Heliyon Vol. 6; no. 5; p. e03947
• Main Authors: Anan, Madoka, Higa, Ryoko, Shikano, Kenshiro, Shide, Masahito, Soda, Akinobu, Carrasco Apolinario, Magdeline E., Mori, Kenji, Shin, Toshitaka, Miyazato, Mikiya, Mimata, Hiromitsu, Hikida, Takatoshi, Hanada, Toshikatsu, Nakao, Kazuwa, Kangawa, Kenji, Hanada, Reiko
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.05.2020; Elsevier
• Subjects: Addiction medicine; Behavioral medicine; Biological psychiatry; BLA; Brain reward system; c-Fos; Cocaine; CPP test; CPu; Endocrinology; Mouse; NAc; Neuromedin U; Neuropeptide; Neuroscience; Physiology; c-Fos; CPu; Brain reward system; Neuropeptide; Biological psychiatry; Neuromedin U; NAc; CPP test; Neuroscience; Mouse; BLA; Behavioral medicine; Physiology; Cocaine; Endocrinology; Addiction medicine
• ISSN: 2405-8440; 2405-8440
• DOI: 10.1016/j.heliyon.2020.e03947

Neuromedin U (NMU) is a bioactive neuropeptide, highly distributed in the gastrointestinal tract and the central nervous system. NMU has various physiological functions related to feeding behavior, energy metabolism, stress responses, circadian rhythmicity and inflammation. Recently, several reports indicate that the central NMU system plays an important role in the reward systems in the brain. However, the underlying molecular mechanisms are not yet fully defined. In this study, we found that some of cocaine-induced c-Fos immunoreactive cells were co-localized with NMU in the nucleus accumbens (NAc), caudate putamen (CPu), and basolateral amygdala (BLA), which are key brain regions associated with the brain reward system, in wild type mice. Whereas, a treatment with cocaine did not influence the kinetics of NMU or NMU receptors mRNA expression in these brain regions, and NMU-knockout mice did not show any higher preference for cocaine compared with their control mice. These results indicate that cocaine has some effect on NMU expressing neurons related to the brain reward system, and this suggests NMU system may have a role on the brain reward systems activated by cocaine. Neuroscience; Physiology; Endocrinology; Addiction Medicine; Behavioral Medicine; Biological Psychiatry; Neuromedin U; neuropeptide; cocaine; c-fos; brain reward system; NAc; CPu; BLA; CPP test; mouse