Short exposure to cadmium disrupts the olfactory system of zebrafish (Danio rerio) - Relating altered gene expression in the olfactory organ to behavioral deficits.

Short exposure to cadmium disrupts the olfactory system of zebrafish (Danio rerio) - Relating altered gene expression in the olfactory organ to behavioral deficits. Aquat Toxicol. 2020 Jun 29;226:105555 Authors: Volz SN, Hausen J, Nachev M, Ottermanns R, Schiwy S, Hollert H Abstract Fish strongly rely on olfaction as a variety of essential behaviors such as foraging and predator avoidance are mediated by the olfactory system. Cadmium (Cd) is known to impair olfaction and accumulate in the olfactory epithelium (OE) and bulb (OB) of fishes. In the present study, the acute toxicity of Cd on olfaction in zebrafish (Danio rerio) was characterized on the molecular and behavioral level. To this end, quantitative real-time PCR was performed in order to analyze the expression of selected genes in both the OE and OB. Moreover, the response of zebrafish to an alarm cue was investigated. Following 24 h of exposure to Cd, the expression of genes associated with olfactory sensory neurons was reduced in the OE. Furthermore, the antioxidant genes peroxiredoxin 1 (prdx1) and heme oxygenase 1 (hmox1), as well as the metallothionein 2 gene (mt2) were upregulated in the OE, whereas hmox1 and the stress-inducible heat shock protein 70 gene (hsp70) were upregulated in the OB upon exposure to Cd. Following stimulation with a conspecific skin extract, zebrafish displayed a considerable disruption of the antipredator behavior with increasing Cd concentration...
Source: Aquatic Toxicology - Category: Toxicology Authors: Tags: Aquat Toxicol Source Type: research