title: Vibrissal paralysis produces increased corticosterone levels and impairment of spatial memory retrieval.
abstract: This research was aimed at establishing how the absence of active whisking in rats affects acquisition and recovery of spatial memory. The mystacial vibrissae were irreversibly paralyzed by cutting the facial nerve's mandibular and buccal branches bilaterally in the facial nerve lesion group (N=14); control animals were submitted to sham-surgery (N=15). Sham-operated (N=11) and facial nerve-lesioned (N=10) animals were trained (one session, eight acquisition trials) and tested 24h later in a circular Barnes maze. It was found that facial nerve lesioned-animals adequately acquired the spatial task, but had impaired recovery of it when tested 24h after training as compared to control ones. Plasma corticosterone levels were measured after memory testing in four randomly chosen animals of each trained group and after a single training trial in the maze in additional facial nerve-lesioned (N=4) and sham-operated animals (N=4). Significant differences respecting the elevation of corticosterone concentration after either a single training trial or memory testing indicated that stress response was enhanced in facial nerve-lesioned animals as compared to control ones. Increased corticosterone levels during training and testing might have elicited the observed whisker paralysis-induced spatial memory retrieval impairment.
authors.affiliation: Behavioral Neurophysiology Laboratory, Universidad Nacional de Colombia, Bogotá, Colombia; Neurosciences Laboratory, Psychology Department, School of Human Sciences, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: William E
authors.initials: WE
authors.lastname: Patarroyo
authors.affiliation: Behavioral Neurophysiology Laboratory, Universidad Nacional de Colombia, Bogotá, Colombia; Neurosciences Laboratory, Psychology Department, School of Human Sciences, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Milady
authors.initials: M
authors.lastname: García-Perez
authors.affiliation: Behavioral Neurophysiology Laboratory, Universidad Nacional de Colombia, Bogotá, Colombia; Neurosciences Laboratory, Psychology Department, School of Human Sciences, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Marisol
authors.initials: M
authors.lastname: Lamprea
authors.affiliation: Behavioral Neurophysiology Laboratory, Universidad Nacional de Colombia, Bogotá, Colombia; Physiological Sciences Department, School of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia.
authors.forename: Alejandro
authors.initials: A
authors.lastname: Múnera
authors.affiliation: Behavioral Neurophysiology Laboratory, Universidad Nacional de Colombia, Bogotá, Colombia; Biology Department, School of Science, Universidad Nacional de Colombia, Bogotá, Colombia. Electronic address: jtroncoso@unal.edu.co.
authors.forename: Julieta
authors.initials: J
authors.lastname: Troncoso
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight / Q000502:physiology; D003345:Corticosterone / Q000097:blood*; D004195:Disease Models, Animal; D005158:Facial Paralysis / Q000097:blood* / Q000150:complications*; D008297:Male; D018782:Maze Learning / Q000502:physiology; D008569:Memory Disorders / Q000209:etiology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar
chemical_list: D003345:Corticosterone
keywords: Barnes circular maze; Corticosterone; Rat; Spatial memory; Stress; Vibrissae