title: Cortisol influences the antipredator behavior induced by chemical alarm cues in the Frillfin goby.
abstract: We evaluated the effect of increased plasma cortisol levels on fish antipredator behavior induced by conspecific chemical alarm cues. The experimental model for the study was the Frillfin goby Bathygobius soporator. We first confirmed that the alarm substance induces typical defensive antipredator responses in Frillfin gobies and described their alarm substance cells (epidermal 'club' cells). Second, we confirmed that intraperitoneal cortisol implants increase plasma cortisol levels in this species. We then demonstrated that exogenous cortisol administration and subsequent exposure to an alarm substance decreased swimming activity to a greater extent than the activity prompted by either stimulus alone. In addition, cortisol did not abolish the sheltering response to the alarm chemical cue even though it decreased activity. As predators use prey movements to guide their first contact with the prey, a factor that decreases swimming activity clearly increases the probability of survival. Consequently, this observation indicates that cortisol helps improve the antipredator response in fish.
authors.affiliation: Departamento de Fisiologia, Instituto de Biociências, UNESP - Univ. Estadual Paulista, Caunesp, Campus de Botucatu - Rubião Jr., 18618-970 Botucatu, São Paulo, Brazil. Electronic address: rebarreto@yahoo.com.
authors.forename: Rodrigo Egydio
authors.initials: RE
authors.lastname: Barreto
authors.affiliation: Laboratório de Neurofisiologia Comparada, Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, USP, Av. Bandeirantes 3900, Monte Alegre, 14049-900 Ribeirão Preto, São Paulo, Brazil.
authors.forename: Augusto
authors.initials: A
authors.lastname: Barbosa-Júnior
authors.affiliation: Departamento de Morfologia e Fisiologia Animal, Faculdade de Ciências Agrárias e Veterinárias, Caunesp, UNESP - Univ. Estadual Paulista, Via de Acesso Prof. Paulo Donato Castelane, 14884-900 Jaboticabal, São Paulo, Brazil.
authors.forename: Elisabeth Criscuolo
authors.initials: EC
authors.lastname: Urbinati
authors.affiliation: Laboratório de Neurofisiologia Comparada, Departamento de Fisiologia, Faculdade de Medicina de Ribeirão Preto, USP, Av. Bandeirantes 3900, Monte Alegre, 14049-900 Ribeirão Preto, São Paulo, Brazil.
authors.forename: Anette
authors.initials: A
authors.lastname: Hoffmann
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology*; D000078404:Epidermal Cells; D006854:Hydrocortisone / Q000008:administration & dosage / Q000097:blood* / Q000494:pharmacology; D010473:Perciformes / Q000502:physiology*; D010675:Pheromones / Q000494:pharmacology; D013268:Stimulation, Chemical
chemical_list: D010675:Pheromones; D006854:Hydrocortisone
keywords: Antipredator behavior; Chemical alarm cue; Communication; Cortisol; Stress