title: Evidence for a histaminergic input from the ventral tuberomammillary nucleus to the solitary tract nucleus involved in arterial pressure regulation.
abstract: The tuberomammillary nucleus (TMN) of the posterior hypothalamus has a high density of histaminergic neurons, the projection fibers of which are present in many areas of the brain, including the nucleus tractus solitarius (NTS), which controls arterial pressure (AP). In this study, we investigated whether the TMN-NTS pathway is involved in central cardiovascular regulation. Bicuculline, a gamma-aminobutyric acid type A (GABAA) receptor antagonist, was microinjected into the ventral TMN of anesthetized rats and its effects on AP and heart rate (HR) were observed. We also evaluated the effect of cetirizine, an H1receptor antagonist, microinjected into the NTS on cardiovascular responses induced by electrical stimulation of the TMN Both AP and HR increased following bicuculline microinjection into the ventral TMN Similar pressor and tachycardic responses were observed after electrical stimulation of the ventral TMN Microinjection of cetirizine into the NTS partially inhibited the pressor response but had no effect on HR Finally, the treadmill test was associated with a high level of c-Fos expression in both ventral TMN and NTS neurons. These results suggest that the TMN-NTS pathway is involved in regulation of AP, presumably under a high-arousal phase, such as that during exercise.
authors.affiliation: Department of Physiology, School of Health and Sports Science Juntendo University, Chiba, Japan.
authors.forename: Ko
authors.initials: K
authors.lastname: Yamanaka
authors.affiliation: Department of Biology, Faculty of Science Ochanomizu University, Tokyo, Japan.
authors.forename: Sabine S
authors.initials: SS
authors.lastname: Gouraud
authors.affiliation: Department of Therapeutic Health Promotion, Kansai University of Health Sciences, Osaka, Japan.
authors.forename: Miwa
authors.initials: M
authors.lastname: Takagishi
authors.affiliation: Department of Physiology, Wakayama Medical University School of Medicine, Wakayama, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kohsaka
authors.affiliation: Department of Physiology, Wakayama Medical University School of Medicine, Wakayama, Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Maeda
authors.affiliation: Department of Physiology, Graduate School of Health and Sports Science Juntendo University, Chiba, Japan hwaki@juntendo.ac.jp.
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Waki
mesh_terms: D000818:Animals; D062186:Arterial Pressure / Q000187:drug effects*; D001640:Bicuculline / Q000494:pharmacology; D017332:Cetirizine / Q000494:pharmacology*; D058787:GABA-A Receptor Antagonists / Q000494:pharmacology; D006339:Heart Rate / Q000187:drug effects*; D006634:Histamine H1 Antagonists / Q000494:pharmacology*; D007026:Hypothalamic Area, Lateral / Q000187:drug effects*; D008297:Male; D009434:Neural Pathways / Q000187:drug effects; D009474:Neurons / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D017552:Solitary Nucleus / Q000187:drug effects*
chemical_list: D058787:GABA-A Receptor Antagonists; D006634:Histamine H1 Antagonists; D001640:Bicuculline; D017332:Cetirizine
keywords: Arterial pressure; histamine; nucleus tractus solitarius; tuberomammillary nucleus