Behavioral and neurotoxic effects of arsenic exposure in zebrafish (Danio rerio, Teleostei: Cyprinidae)

Abstract

This study investigated the passive avoidance conditioning in zebrafish (Danio rerio). An instrument was developed for measuring escape responses triggered by a conditioned stimulus. This system allowed quantification of latency of crossing from a light to a dark zone. Zebrafish were trained to swim from an illuminated to a dark compartment, where they received a body shock (training session). The proposed methodology was efficient for evaluation of working, short, and long-term memory formation of an aquatic animal model. The possibility of employing memory measurements in toxicity tests, in order to obtain an ecologically meaningful biomarker response, was also analyzed. In this experiment, immediately after the training session, fish were exposed to three arsenic (As(V)) concentrations. After the test session, the brain was removed for biochemical analyses. A control group was kept in tap water. After exposure, animals were submitted to a one-trial inhibitory avoidance test for measurement of long-term memory (LTM). Results from behavioral and biochemical analyses showed that the three As(V) concentrations impaired LTM (p<0.05) and increased protein oxidation, which suggests an amnesic and pro-oxidant effect of As(V). Evaluation of behavior parameters in aquatic models is an important complement in studies concerning the environmental impact of chemical substances.

Pathophysiological Changes in Rohu (Labeo rohita, Hamilton) Fingerlings Following Arsenic Exposure

“…Caudal bending was noticed in the fishes exposed C10 ppm, with time, which greatly retarded the normal swimming pattern. The behavioral alteration due to arsenic toxicity in zebrafish (Danio rerio) has been reported earlier [15]. Hyper excitability, loss of equilibrium and sinking to the bottom of aquarium and staying motionless are the prime behavioral changes observed, which corroborates with the observations made in earlier reports [15,16].…”

“…The behavioral alteration due to arsenic toxicity in zebrafish (Danio rerio) has been reported earlier [15]. Hyper excitability, loss of equilibrium and sinking to the bottom of aquarium and staying motionless are the prime behavioral changes observed, which corroborates with the observations made in earlier reports [15,16]. In an earlier study it was suggested that caudal bending, which greatly retarded the normal swimming pattern in the experimental fishes, could be due to the inhibition of acetylcholinesterase (AChE) [16].…”

Zebrafish for the Study of the Biological Effects of Nicotine

“…This dopamine (DA) metabolite, created during DA synaptic reuptake, acts as a DA level surrogate and suggests that potentiated release of DA following nicotine exposure is linked to cognitive improvements ). The cognitive stimulation of nicotine and its mitigation by preadministration of mecamylamine was also observed in a study of memory using a place preference assay (de Castro et al, 2009). Many similar studies have also been carried out using mammalian models.…”

Essential oil ofPsidium cattleianumleaves: Antioxidant and antifungal activity

“…Excessive production of free radicals can generate a lipid peroxidation chain reaction, which are responsible for many pathological disorders (Castro et al, 2009).…”