May 2019 DOI 10.14302/issn.2637-6075.jpae-19-2779
Chibueze Izah SylvesterCorresponding author
Department of Biological Sciences, Bayelsa Medical University, Yenagoa, Bayelsa State, Nigeria.
This study evaluated the behavioural response and toxicity of paraquat dichloride to fingerlings of Clariasgariepinus. The fishes were acclimatized for 14 days and exposed to sublethal concentration of 0.00 ppm, 16.56 ppm, 22.08 ppm, 27.60 ppm, 33.12 ppm and 38.64 ppm. A 24 hours’ renewal bioassay was adopted in this study. Results showed that the fishes exhibited change in swimming, opercular movement, body pigmentation, surfacing and air gulping. Mortality rate increased significantly at p<0.05 as the concentration of the toxicant increased as well as the exposure period. LC50 values at 24, 48, 72 and 96 were 59.95, 47.59, 38.12 and 26.18ppm, respectively. Based on the results, Paraquat dichloride users need to discard the remains of empty cans properly to avoid contamination. Also there is need to exercise caution when using paraquat dichloride based herbicides in agricultural fields close to surface water resources.
Mar 2020 DOI 10.14302/issn.2577-2279.ijha-20-3215
O. Atinuke AnjorinCorresponding author
Department of Anatomy and Cell Biology
Since oxidative stress impairs the cardiovascular function, the hypothesis from the present study is that the treatment of paraquat-exposed adult Wistar rats with methanolic extract of Abelmoschus esculentusseed would reduce paraquat-induced cardiovascular damage. Thirty healthy female Wistar rats weighing 120-150 g were randomly assigned into 6 groups of 5 rats each (Groups A, B, C, D, E and F). Rats in groups A served as control and received normal saline while groups B, C, D, E and F received a single dose of paraquat (7mgkg-1i.p.). Rats in group B was sacrificed 24hours following paraquat administration while daily administration of 100 mg kg-1and 200 mg kg-1 of methanolic extract of Abelmoschus esculentusseed extract were given orally to groups C and D while group E received daily oral dose of Vitamin E at 100mgkg-1 and group F was left untreated. Histological and biochemical preparations of the heart was made and data were expressed as mean± SEM. Significant difference was set at p<0.05. Results showed no significance difference (p<0.05) in nitric oxide activity, Glutathione reductase activity, and troponin I activity across the paraquat-exposed groups when compared with control. Histological studies reveal distortion of normal cardiac histo-architecture in paraquat-exposed group B compared with control rats while Abelmoschus esculentus reversed these changes in other treated groups. The study concluded that paraquat caused significant distortion of the cardiac histo-architecture and methanolic extract of immature Abelmoschus esculentus seed had antioxidant and ameliorative effects similar to Vitamin E on paraquat-induced myocardial injury.