title: Cellular prion protein modulates defensive attention and innate fear-induced behaviour evoked in transgenic mice submitted to an agonistic encounter with the tropical coral snake Oxyrhopus guibei.
abstract: The cellular prion protein (PrP(C)) is a neuronal anchored glycoprotein that has been associated with distinct functions in the CNS, such as cellular adhesion and differentiation, synaptic plasticity and cognition. Here we investigated the putative involvement of the PrP(C) in the innate fear-induced behavioural reactions in wild-type (WT), PrP(C) knockout (Prnp(0/0)) and the PrP(C) overexpressing Tg-20 mice evoked in a prey versus predator paradigm. The behavioural performance of these mouse strains in olfactory discrimination tasks was also investigated. When confronted with coral snakes, mice from both Prnp(0/0) and Tg-20 strains presented a significant decrease in frequency and duration of defensive attention and risk assessment, compared to WT mice. Tg-20 mice presented decreased frequency of escape responses, increased exploratory behaviour, and enhancement of interaction with the snake, suggesting a robust fearlessness caused by PrP(C) overexpression. Interestingly, there was also a discrete decrease in the attentional defensive response (decreased frequency of defensive alertness) in Prnp(0/0) mice in the presence of coral snakes. Moreover, Tg-20 mice presented an increased exploration of novel environment and odors. The present findings indicate that the PrP(C) overexpression causes hyperactivity, fearlessness, and increased preference for visual, tactile and olfactory stimuli-associated novelty, and that the PrP(c) deficiency might lead to attention deficits. These results suggest that PrP(c) exerts an important role in the modulation of innate fear and novelty-induced exploration.
authors.affiliation: Laboratory of Neuroanatomy & Neuropsychobiology, Department of Pharmacology, School of Medicine of Ribeirão Preto of the University of São Paulo (USP), Av. dos Bandeirantes 3900, Ribeirão Preto, São Paulo (SP), 14049-900, Brazil.
authors.forename: Bruno
authors.initials: B
authors.lastname: Lobão-Soares
authors.forename: Roger
authors.initials: R
authors.lastname: Walz
authors.forename: Rui Daniel Schröder
authors.initials: RD
authors.lastname: Prediger
authors.forename: Renato Leonardo
authors.initials: RL
authors.lastname: Freitas
authors.forename: Fabrício
authors.initials: F
authors.lastname: Calvo
authors.forename: Marino Muxfeldt
authors.initials: MM
authors.lastname: Bianchin
authors.forename: João Pereira
authors.initials: JP
authors.lastname: Leite
authors.forename: Michele Christine
authors.initials: MC
authors.lastname: Landemberger
authors.forename: Norberto Cysne
authors.initials: NC
authors.lastname: Coimbra
mesh_terms: D000378:Agonistic Behavior / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001288:Attention / Q000502:physiology*; D001522:Behavior, Animal; D017815:Elapidae; D004924:Escape Reaction / Q000502:physiology; D005239:Fear; D007323:Instinct; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D018621:PrPC Proteins / Q000172:deficiency / Q000378:metabolism*
chemical_list: D018621:PrPC Proteins