title: Integrity of the dorsolateral periaqueductal grey is essential for the fight-or-flight response, but not the respiratory component of a defense reaction.
abstract: Periaqueductal grey is believed to be one of the key structures of the central respiratory stress network. Previous studies established that stimulation of the periaqueductal grey, especially its dorsolateral division (dlPAG), evokes tachypnea as well as increases in other autonomic parameters and motor activity. We investigated the effects of blockade of the dlPAG with GABAA agonist muscimol on respiration during stress and presentation of brief alerting stimuli in conscious unrestrained rats. We found that integrity of the dlPAG is not essential for stress-induced increase in basal/resting respiratory rate or for generation of respiratory responses to brief alerting stimuli. However, blockade of the dlPAG reduced the amount of motor activity and concomitant high-frequency respiratory activity during restraint and the first 5min of novelty stress. We conclude that the integrity of the dlPAG is not essential for generation of respiratory component of the defense reaction, but it mediates expression of the fight-or-flight response including its respiratory component.
authors.affiliation: University of Newcastle, Callaghan, NSW, Australia. Electronic address: ebondarenko@g.ucla.edu.
authors.forename: E
authors.initials: E
authors.lastname: Bondarenko
authors.affiliation: Biotechnology Centre, Federal University of Paraiba, João Pessoa, PB, Brazil.
authors.forename: D D
authors.initials: DD
authors.lastname: Guimarães
authors.affiliation: Biotechnology Centre, Federal University of Paraiba, João Pessoa, PB, Brazil.
authors.forename: V A
authors.initials: VA
authors.lastname: Braga
authors.affiliation: University of Newcastle, Callaghan, NSW, Australia.
authors.forename: E
authors.initials: E
authors.lastname: Nalivaiko
mesh_terms: D000374:Aggression / Q000187:drug effects / Q000502:physiology; D000818:Animals; D001143:Arousal / Q000187:drug effects / Q000502:physiology*; D002408:Catheters, Indwelling; D058787:GABA-A Receptor Antagonists / Q000494:pharmacology; D008297:Male; D023421:Models, Animal; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D009118:Muscimol / Q000494:pharmacology; D010487:Periaqueductal Gray / Q000187:drug effects / Q000503:physiopathology*; D010775:Photic Stimulation; D010991:Plethysmography; D011897:Random Allocation; D017208:Rats, Wistar; D011963:Receptors, GABA-A / Q000378:metabolism; D012119:Respiration / Q000187:drug effects; D012149:Restraint, Physical; D013315:Stress, Psychological / Q000503:physiopathology*
chemical_list: D058787:GABA-A Receptor Antagonists; D011963:Receptors, GABA-A; D009118:Muscimol
keywords: Arousal; Periaqueductal grey; Respiration; Stress