title: Experimental studies of remarkable monoamine releases and neural resistance to the transient ischemia and reperfusion.
abstract: BACKGROUND
  The literature described that neural damage caused by ischemia definitely occurs in brain areas. However, few studies have shown real-time changes of extracellular monoamine levels at the time of transient ischemia.
  
  
  METHODS
  We examined changes in the responses of dopamine (DA) and serotonin (5-HT) release in the nucleus accumbens (ACC) of rats treated with four-vessel occlusion (4VO) in experiment 1. In the second experiment, we investigated the selective neural vulnerabilities among the ACC, lateral hypothalamus (LH), and frontal cortex (FC) of rats treated with 4VO and four days of reperfusion.
  
  
  RESULTS
  The extracellular levels of DA and 5-HT were remarkably increased 200- and 20-fold upon the 10-min clipping of both common carotid arteries in transient cerebral ischemia, respectively. Each increased monoamine release returned to the baseline levels immediately. The release of DA in the ACC and FC was significantly decreased in the rats treated with the coagulation of bilateral vertebral arteries (2VO), compared with that of sham-operated rats. K(+)-induced DA release in the ACC and FC of 4VO-treated rats was increased without alteration of DA content.
  
  
  CONCLUSIONS
  Surviving dopaminergic neurons in the ACC and FC showed neural hyperfunction associated with the monoamine release, serotonergic neurons in particular these areas exhibiting functional resistance to the transient ischemic change.
  
  
  CONCLUSIONS
  It is suggested that the remarkable extracellular release of DA and 5-HT was not the cause of the ischemic delayed neural degeneration in each brain area, and that the functions of neurotransmitter release involved remarkable resistance to the transient ischemia.
authors.affiliation: Department of Food Sciences and Biotechnology, Faculty of Life Sciences, Hiroshima Institute of Technology, Miyake, Saeki-ku, Hiroshima 731-5193, Japan; Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University Faculty of Medicine, Kasumi, Minami-ku, Hiroshima 734-8551, Japan. Electronic address: k.yoshimoto.ud@it-hiroshima.ac.jp.
authors.forename: Kanji
authors.initials: K
authors.lastname: Yoshimoto
authors.affiliation: Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University Faculty of Medicine, Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Namera
authors.affiliation: Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University Faculty of Medicine, Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Arima
authors.affiliation: Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University Faculty of Medicine, Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Nagao
authors.affiliation: Department of Forensic Medicine, Kyoto Prefectural University of Medicine, Kawaramachi, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Hiroh
authors.initials: H
authors.lastname: Saji
authors.affiliation: Department of Forensic Medicine, Kyoto Prefectural University of Medicine, Kawaramachi, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Takasaka
authors.affiliation: Department of Forensic Medicine, Kyoto Prefectural University of Medicine, Kawaramachi, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Uemura
authors.affiliation: Department of Basic Geriatrics, Kyoto Prefectural University of Medicine, Kawaramachi, Kamigyo-ku, Kyoto 602-8566, Japan.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Watanabe
authors.affiliation: Department of Histology and Neurobiology, Dokkyo University School of Medicine, Mibu, Tochigi 321-0293, Japan.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Ueda
authors.affiliation: Department of Forensic Medicine, Institute of Biomedical and Health Sciences, Hiroshima University Faculty of Medicine, Kasumi, Minami-ku, Hiroshima 734-8551, Japan.
authors.forename: Masataka
authors.initials: M
authors.lastname: Nagao
keywords: Dopamine; Four-vessel occlusion; Ischemia; Reperfusion; Serotonin