The sensory-motor responses to environmental acidosis in larval zebrafish: Influences of neurotransmitter and water chemistry. (November 2019)

• Record Type: Journal Article
• Authors: JavadiEsfahani, Raha; Kwong, Raymond W.M.
• Is Part Of: Chemosphere. Volume 235(2019)
• Page Start: 383
• Page End: 390
• Publication Date: 2019-11
• Subjects: Freshwater acidification -- Larval fish -- Touch-evoked escape response -- Water chemistry -- Neurotransmitter; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2019.06.133
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: The sensory-motor function in larval zebrafish ( Danio rerio ) following exposure to low water pH was investigated. The results suggested that acid exposure (pH 4.0–5.0; control: pH 7.4) significantly reduced the touch-evoked escape response of larval zebrafish at 3 days post fertilization (dpf). A significant number of pH 4.0-exposed larvae also exhibited a lack of escape response. Treatment with neurotransmitters showed that serotonin or acetylcholine, but not dopamine, reduced the adverse effects of acid exposure on the escape response of larvae. Co-exposure to serotonin and acetylcholine did not further improve the escape response of acid-exposed larvae, suggesting no additive effect by these neurotransmitters. Interestingly, the negative effects of acid exposure on the escape response could be completely rescued by elevating the water levels of Ca 2+, but not NaCl. Collectively, these results suggested that acid-induced disruption in Ca 2+ balance suppressed the serotonin- and acetylcholine-mediated neuronal signaling, thereby affecting the sensory-motor function and escape response of larval zebrafish. Findings from the present study may have important implication for the survival (e.g., escape from adverse conditions) of larval fish in acid-impacted environments, particularly during early development when they are still incapable of spontaneous swimming. Graphical abstract: Image 1 Highlights: Exposure to low water pH negatively affects the escape bebaviour of zebrafish larvae. Treatment with specific neurotransmitters partially rescues the acid-induced effects. Elevation in water calcium level can completely restore the escape behavior.