Electrophysiological responses in Amazonian fish species Bryconops caudomaculatus (Osteichthyes: Characiformes) as biomarkers of xenobiotic toxicity.
Comp Biochem Physiol C Toxicol Pharmacol
; 228: 108653, 2020 Feb.
Article
en En
| MEDLINE
| ID: mdl-31683014
Sublethal exposures to environmental pollutants may cause changes in physiological parameters. Thus, knowledge of basal physiological rates of the species and the development of methods to quantify these rates are extremely important. Considering the scarcity of cardiac and muscle physiological studies in native Amazonian fish species and that no evaluation of electrophysiological responses by exposure to a stressor has been reported in Bryconops caudomaculatus, the aim of this study was to develop techniques of electromyographic and electrocardiographic recordings of normal responses, during toxicity induction and short-term recovery. A total of 9 animals were used, divided into two groups: control group (nâ¯=â¯4) and treated group (nâ¯=â¯5), with records lasting 5â¯min. The results showed that the basal electromyographic records indicate that the studied species has a very intense swimming activity, whereas the basal cardiac parameters clearly showed the patterns in P wave tracing, QRS complex, T wave and Q-T and R-R intervals. During exposure to the stressor, muscle activity ceased presenting intense decrease and myorelaxant effect expected. Electrocardiographic responses confirmed cardiotoxicity with intense bradycardia, ventricular bigeminism, prolongation of QRS complex duration and cardiac arrhythmias, indicating cardiac dysfunction. It was concluded that the electrophysiological responses are excellent biomarkers and showed the susceptibility of the species to the tested substance. In addition, the electrocardiogram and the electromyogram are excellent techniques to reflect the degree of environmental stress when organisms are exposed to toxic substances in the environment.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Contaminantes Químicos del Agua
/
Xenobióticos
/
Electrocardiografía
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Electromiografía
/
Characiformes
Límite:
Animals
Idioma:
En
Revista:
Comp Biochem Physiol C Toxicol Pharmacol
Asunto de la revista:
FARMACOLOGIA
/
TOXICOLOGIA
Año:
2020
Tipo del documento:
Article
País de afiliación:
Brasil
Pais de publicación:
Estados Unidos