Bernardo Baldisserotto1, Thaylise V Parodi2, E Don Stevens3. 1. Departamento de Fisiologia e Farmacologia, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil. Electronic address: bbaldisserotto@hotmail.com. 2. Departamento de Fisiologia e Farmacologia, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil. 3. Department of Biomedical Sciences, Atlantic Veterinary College, University of Prince Edward Island, Charlottetown, PEI, Canada.
Abstract
OBJECTIVE: To test the postexposure analgesic efficacy of low doses of eugenol in zebrafish. STUDY DESIGN: Prospective experimental study. ANIMALS: A total of 76 large adult zebrafish (Danio rerio). METHODS: Fish swimming behavior (median velocity, freeze time, high-speed swimming and distance moved in the vertical direction) was recorded in a 1.6 L video arena before and after exposure to eugenol (0, 1, 2, 5, 10 and 20 mg L-1). In a second experiment, fish were anesthetized with 2-phenoxy-ethanol and treated with an injection of 5% acetic acid (noxious stimulus), and then exposed to 0, 1, 2 and 5 mg L-1 eugenol. The fish swimming behavior was also recorded. RESULTS: The higher doses (10 and 20 mg L-1) reduced the median velocity, high-speed swimming and distance moved in the vertical direction, and increased the freeze time. Zebrafish behavior was not altered by eugenol (1, 2 and 5 mg L-1) after noxious stimulation. CONCLUSIONS AND CLINICAL RELEVANCE: The change in the behavior of zebrafish associated with a noxious stimulus can be monitored and is a good model for studying analgesia in fish. Eugenol (10 and 20 mg L-1) induced zebrafish sedation. The response after a noxious stimulus was not affected by postexposure to lower doses, and thus we cannot recommend its use as an analgesic.
OBJECTIVE: To test the postexposure analgesic efficacy of low doses of eugenol in zebrafish. STUDY DESIGN: Prospective experimental study. ANIMALS: A total of 76 large adult zebrafish (Danio rerio). METHODS: Fish swimming behavior (median velocity, freeze time, high-speed swimming and distance moved in the vertical direction) was recorded in a 1.6 L video arena before and after exposure to eugenol (0, 1, 2, 5, 10 and 20 mg L-1). In a second experiment, fish were anesthetized with 2-phenoxy-ethanol and treated with an injection of 5% acetic acid (noxious stimulus), and then exposed to 0, 1, 2 and 5 mg L-1 eugenol. The fish swimming behavior was also recorded. RESULTS: The higher doses (10 and 20 mg L-1) reduced the median velocity, high-speed swimming and distance moved in the vertical direction, and increased the freeze time. Zebrafish behavior was not altered by eugenol (1, 2 and 5 mg L-1) after noxious stimulation. CONCLUSIONS AND CLINICAL RELEVANCE: The change in the behavior of zebrafish associated with a noxious stimulus can be monitored and is a good model for studying analgesia in fish. Eugenol (10 and 20 mg L-1) induced zebrafish sedation. The response after a noxious stimulus was not affected by postexposure to lower doses, and thus we cannot recommend its use as an analgesic.
Authors: Ahmed K Kammoun; Alaa Khedr; Maha A Hegazy; Ahmed J Almalki; Khaled M Hosny; Walaa A Abualsunun; Samar S A Murshid; Rana B Bakhaidar Journal: Drug Deliv Date: 2021-12 Impact factor: 6.419
Authors: Faiyaz Shakeel; Prawez Alam; Abuzer Ali; Mohammed H Alqarni; Abdullah Alshetaili; Mohammed M Ghoneim; Sultan Alshehri; Amena Ali Journal: Molecules Date: 2021-12-02 Impact factor: 4.411