Autonomic and cardiovascular effects of central neuromedin U in rats.
Previous studies have demonstrated that neuromedin U (NMU) affects cardiovascular functions such as blood pressure (BP) or heart rate (HR) in rats. Here, we examined the effects of the lateral cerebral ventricular (ICV) injection of various doses of NMU on renal sympathetic nerve activity (RSNA) and BP in urethane-anesthetized rats. ICV injection of NMU elevated RSNA, BP and HR in a dose-dependent manner. Moreover, neither ICV pretreatment of thioperamide, an antagonist of histaminergic H3-receptor, or of diphenhydramine, an antagonist of histaminergic H1-receptor, abolished increasing effects of NMU on RSNA, BP and HR In addition, ICV injection of NMU suppressed gastric vagal nerve activity (GVNA) and activated brown adipose tissue sympathetic nerve activity (BAT-SNA) of anesthetized rats, and elevated brown adipose tissue temperature (BAT-T) of conscious rats. Thus, these evidence suggest that NMU affects neural activities of autonomic nerves containing RSNA, GVNA or BAT-SNA, and BP by mediating central mechanism.
Tanida
Mamoru
M
Department of Biomedical Sciences, College of Life Sciences, Ritsumeikan University, Kusatsu, Shiga, 525-8577, Japan. mtanida@sk.ritsumei.ac.jp
Satomi
Jun
J
Shen
Jiao
J
Nagai
Katsuya
K
D000704:Analysis of Variance; D000818:Animals; D001341:Autonomic Nervous System / Q000187:drug effects*; D001794:Blood Pressure / Q000187:drug effects; D001831:Body Temperature / Q000187:drug effects; D002319:Cardiovascular System / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects; D054828:Histamine H3 Antagonists / Q000494:pharmacology; D007276:Injections, Intraventricular / Q000379:methods; D007668:Kidney / Q000187:drug effects; D008297:Male; D009479:Neuropeptides / Q000494:pharmacology*; D010880:Piperidines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013686:Telemetry / Q000379:methods; D013997:Time Factors
D054828:Histamine H3 Antagonists; D009479:Neuropeptides; D010880:Piperidines; C056900:neuromedin U; C052075:thioperamide