title: Conspecific alarm substance differently alters group behavior of zebrafish populations: Putative involvement of cholinergic and purinergic signaling in anxiety- and fear-like responses.
abstract: The zebrafish (Danio rerio) is an emergent model organism for assessing fear and anxiety-like phenotypes. The short fin wild type (WT), and leopard (leo) are two zebrafish populations that present several behavioral differences, in which leo displays pronounced defensive responses. Mounting evidence suggests a modulatory role for cholinergic and purinergic signaling in fear and anxiety, but the involvement of these neurotransmitter systems in the behavioral profile of zebrafish is obscure. Here we tested whether the acute exposure to conspecific alarm substance (AS), an experimental protocol that induces fear, alters shoaling behavior, diving response, acetylcholinesterase (AChE) activity, and nucleotide hydrolysis in brain tissue of WT and leo. When four fish were concomitantly exposed to AS extracted from a donor fish of similar phenotype, both populations presented a significant increase of erratic movements without changes in freezing bouts. An increased shoal cohesion and a decreased vertical distribution were observed only in WT exposed to AS. The respective population also revealed a significant increase in AChE and ecto-5'-nucleotidase activities after the exposure period. The comparison of basal endpoints between populations showed that leo displays a higher social cohesion, few vertical transitions and enhanced AChE and ecto-5'-nucleotidase activities. In conclusion, we suggest that the effects of AS on defensive behaviors depend on the population, indicating the existence of distinct neurochemical mechanisms involved. Furthermore, this report shows the first evidence of a potential role of cholinergic and purinergic systems in fear- and anxiety-like responses of zebrafish populations.
authors.affiliation: Laboratory of Experimental Neuropsychobiology, Department of Biochemistry and Molecular Biology, Center of Natural and Exact Sciences, Federal University of Santa Maria, 1000 Roraima Avenue, Santa Maria, RS, 97105-900, Brazil.
authors.forename: Julia
authors.initials: J
authors.lastname: Canzian
authors.affiliation: Laboratory of Experimental Neuropsychobiology, Department of Biochemistry and Molecular Biology, Center of Natural and Exact Sciences, Federal University of Santa Maria, 1000 Roraima Avenue, Santa Maria, RS, 97105-900, Brazil.
authors.forename: Barbara D
authors.initials: BD
authors.lastname: Fontana
authors.affiliation: Laboratory of Experimental Neuropsychobiology, Department of Biochemistry and Molecular Biology, Center of Natural and Exact Sciences, Federal University of Santa Maria, 1000 Roraima Avenue, Santa Maria, RS, 97105-900, Brazil; Graduate Program in Biological Sciences: Toxicological Biochemistry, Federal University of Santa Maria, 1000 Roraima Avenue, Santa Maria, RS, 97105-900, Brazil.
authors.forename: Vanessa A
authors.initials: VA
authors.lastname: Quadros
authors.affiliation: Laboratory of Experimental Neuropsychobiology, Department of Biochemistry and Molecular Biology, Center of Natural and Exact Sciences, Federal University of Santa Maria, 1000 Roraima Avenue, Santa Maria, RS, 97105-900, Brazil; Graduate Program in Biological Sciences: Toxicological Biochemistry, Federal University of Santa Maria, 1000 Roraima Avenue, Santa Maria, RS, 97105-900, Brazil; The International Zebrafish Neuroscience Research Consortium (ZNRC), 309 Palmer Court, Slidell, LA, 70458, USA. Electronic address: dbrosemberg@gmail.com.
authors.forename: Denis B
authors.initials: DB
authors.lastname: Rosemberg
mesh_terms: D015720:5'-Nucleotidase / Q000378:metabolism*; D000110:Acetylcholinesterase / Q000378:metabolism*; D000704:Analysis of Variance; D000818:Animals; D030801:Animals, Genetically Modified; D001007:Anxiety / Q000378:metabolism*; D019540:Area Under Curve; D001522:Behavior, Animal / Q000502:physiology*; D004924:Escape Reaction / Q000502:physiology*; D005239:Fear; D005260:Female; D008297:Male; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D029961:Zebrafish Proteins; D000110:Acetylcholinesterase; D015720:5'-Nucleotidase
keywords: Acetylcholinesterase; Alarm substance; Defensive behavior; Nucleotide hydrolysis; Shoaling; Zebrafish