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Imaging Approaches to Assessments of Toxicological Oxidative Stress Using Genetically-encoded Fluorogenic Sensors
Published on: February 7, 2018
Chronotoxicology of florfenicol
E J Picco1, D C Díaz, S E Valtorta
1Cátedra de Farmacología, Facultad de Ciencias Veterinarias, Universidad Nacional del Litoral, Argentina.
Abstract:
Sixty 3-month-old homozygote male mice were studied for circadian rhythmicity in the toxicity of florfenicol overdose. Animals were kept under a regimen of 12h light, 12h darkness (12:12 LD) with food and water available ad libitum. The LD50 (median lethal) dose was determined in a preliminary experiment and was administered to groups of 10 mice at six different clock times (hours) after light onset (HALO): 0, 4, 8, 12, 16, and 20 HALO. Cosinor analysis verified a statistically significant (P < .04) circadian rhythm in the toxic effect (mortality) of florfenicol. Mortality was greatest when the drug was injected 4h after the commencement of the activity span (16 HALO) and least when injected 4h after the start of the diurnal rest span (4 HALO). Mortality was 2.5 times greater when drug injection was given at 16 HALO than at 4 HALO.
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