Acute central administration of immepip, a histamine H3 receptor agonist, suppresses hypothalamic histamine release and elicits feeding behavior in rats.
Histamine suppresses feeding behavior via histamine H1 receptors in the hypothalamus. This study was performed to examine whether the acute reduction of histamine release in the hypothalamus caused by immepip, a histamine H3 agonist, modulates the feeding behavior of rats. Rats had a catheter implanted in the third cerebral ventricle (i3v) and were given central injections of phosphate-buffered-saline or immepip (100-300 pmol/rat). Following the i3v administration of immepip, the rats developed dose-dependent hypokinesia within 10 min of administration. Next to hypokinesia, the rats showed significant dose-dependent feeding behavior. High-performance liquid chromatography (HPLC) confirmed the reduction in histamine release in the hypothalamus of rats following i3v administration of immepip. These results suggest that i3v administration of immepip, an H3 receptor agonist, suppresses hypothalamic histamine release and elicits feeding behavior in rats.
Chiba
Seiichi
S
Department of Internal Medicine I, School of Medicine, Oita University, 1-1 Idaigaoka, Hasama, Oita 879-5593, Japan. schiba@med.oita-u.ac.jp
Itateyama
Emi
E
Sakata
Toshiie
T
Yoshimatsu
Hironobu
H
D000704:Analysis of Variance; D000818:Animals; D002404:Catheterization; D002851:Chromatography, High Pressure Liquid; D004305:Dose-Response Relationship, Drug; D005247:Feeding Behavior / Q000187:drug effects*; D017442:Histamine Agonists / Q000008:administration & dosage*; D006636:Histamine Release / Q000187:drug effects*; D018476:Hypokinesia / Q000139:chemically induced; D007031:Hypothalamus / Q000187:drug effects* / Q000378:metabolism; D007093:Imidazoles / Q000008:administration & dosage*; D007276:Injections, Intraventricular; D016014:Linear Models; D008297:Male; D008761:Methylhistamines / Q000378:metabolism; D010880:Piperidines / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar; D018100:Receptors, Histamine H3 / Q000378:metabolism*
D017442:Histamine Agonists; D007093:Imidazoles; D008761:Methylhistamines; D010880:Piperidines; D018100:Receptors, Histamine H3; C085755:4-(1H-imidazol-4-ylmethyl)piperidine; C020404:tele-methylhistamine