ABSTRACT
Ethanolic, acetone and petroleum ether extracts from leaves and stems of Lagenaria siceraria [Cucurbitaceae] were screened for their repellency effect against Culex pipiens L. mosquito. The repellent action of the present plant extracts were varied depending on the plant parts and the dose of extract. The petroleum ether extract of leaves showed the same repellency percent [100%] of commercial formulation, N. N.'diethyl toulamide [DEBT] at the higher dose [3.33 mg/cm[2]], while petroleum ether extract from stems exhibiting the repellent action [89.6%] at the same dose, respectively. Ethanolic extracts of leaves and stems exhibited the lowest repellent activity as it recorded [81.3% and 69.1%] at [6.67 mg/cm[2]], respectively. Results of this study may contribute to design an alternative way to control mosquitoes currently based on applications of synthetic insecticides. These extracts could be developed commercially as an effective personal protection measure against mosquito bites and thus to control diseases caused by mosquito-borne pathogens
Subject(s)
Insect Repellents/adverse effectsABSTRACT
The environment includes increasing number of synthetic chemical compounds that cause environmental contamination . One of the most popular contaminating compounds are pyrethroids insecticides .Therefore, their wide spread use in agriculture and puplic health stimulated our attention for studying their possible toxic effect[s] on drug action .Fluoxetine is a selective inhibitor of serotonin reuptake which is widely used as an antidepressant . The aim of this work was to study the effect of inhalational exposure to vapour of two commonly used mosquito repellant preparations containing pyrethroids on the neurobehavioural action of fluoxetine . Sprague Dawley adult male rats were allocated into 3 main groups namely, control, and Ezalo and Ragon exposed groups .Exposure was performed 20 mm/day for 7 days in a static chamber . Twenty four hours later, i.p injection of fluoxetine [10 mg/kg] was performed . Contents of serotonin, norepinephrine and dopamine were determined in differtent brain regions one hour after fluoxetine injection . Behavioural parameters were also determined using open field and swimming test techniques.The obtained results showed that pre-exposure to Ezalo vapour induced significant increase in ambulation and rearing frequencies, while pre-exposure to Ragon vapour induced significant increase in ambulation, grooming and rearing frequencies as compared to fluoxetine-treated animals . Contents of serotonin and dopamine were also significantly altered in most brain regions .The obtained changes in the neurobehavioural parameters may be due to the effect[s] of pyrethroids and or the accompanying substances present in the mosquito repellant preparations on the biotransformation of fluoxetine