title: Increased plasma corticosterone levels after periaqueductal gray stimulation-induced escape reaction or panic attacks in rats.
abstract: The hypothalamo-pituitary-adrenal (HPA) axis is involved in stress, depression and anxiety. Controversy exists on HPA axis activation during panic attacks (PAs). We examined whether the HPA axis is involved in the escape or panic-like response in an animal model of PAs induced by electrical stimulation of the dorsolateral periaqueductal gray (dlPAG) in rats. Additionally, rats were also treated with chronic administration of buspirone (BUSP) and escitalopram (ESCIT), respectively; and they were stimulated in the open-field arena for panic-like reaction. Levels of stress hormone corticosterone were measured following 30 min after escape or panic condition. Our results demonstrated that the levels of plasma corticosterone were significantly increased after the induction of escape or panic-like response in comparison with the sham animals. The levels of corticosterone were significantly decreased in the dlPAG stimulated groups after rats were treated chronically with the ESCIT but not the BUSP as compared to the saline treated animals. Importantly, the increase of corticosterone level after escape or panic-like response was paralleled by an increase of neuronal activation of c-Fos in both the parvocellular and magnocellular paraventricular nucleus of the hypothalamus. Moreover, the c-Fos data also showed a decrease in the number of positive cells particularly for the ESCIT as well as the BUSP in comparison with the saline stimulated animals. In conclusion, the present study clearly demonstrated that PA or escape response activates the HPA axis and it remains difficult to anticipate the mechanism underlying HPA axis during PAs and its relationship with 5-HT drugs.
authors.affiliation: Department of Neuroscience, Maastricht University, The Netherlands. lw.lim@maastrichtuniversity.nl
authors.forename: Lee Wei
authors.initials: LW
authors.lastname: Lim
authors.forename: Arjan
authors.initials: A
authors.lastname: Blokland
authors.forename: Marlies
authors.initials: M
authors.lastname: van Duinen
authors.forename: Veerle
authors.initials: V
authors.lastname: Visser-Vandewalle
authors.forename: Sonny
authors.initials: S
authors.lastname: Tan
authors.forename: Rinske
authors.initials: R
authors.lastname: Vlamings
authors.forename: Mark
authors.initials: M
authors.lastname: Janssen
authors.forename: Ali
authors.initials: A
authors.lastname: Jahanshahi
authors.forename: Mujzgan
authors.initials: M
authors.lastname: Aziz-Mohammadi
authors.forename: Harry W M
authors.initials: HW
authors.lastname: Steinbusch
authors.forename: Koen
authors.initials: K
authors.lastname: Schruers
authors.forename: Yasin
authors.initials: Y
authors.lastname: Temel
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology; D002065:Buspirone / Q000494:pharmacology; D015283:Citalopram / Q000494:pharmacology; D003345:Corticosterone / Q000097:blood*; D004558:Electric Stimulation; D004924:Escape Reaction / Q000187:drug effects / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D008297:Male; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D010200:Panic / Q000187:drug effects / Q000502:physiology*; D010487:Periaqueductal Gray / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology
chemical_list: D014151:Anti-Anxiety Agents; D002065:Buspirone; D015283:Citalopram; D003345:Corticosterone; D016760:Proto-Oncogene Proteins c-fos; D017367:Selective Serotonin Reuptake Inhibitors