Behavioral and neurochemical effects induced by pyrethroid-based mosquito repellent exposure in rat offsprings during prenatal and early postnatal period.
Synthetic pyrethroids, besides their use in agriculture, are prevalently used in our houses as mosquito repellent (MR) in the form of aerosol, mats, coils and liquid vaporizers. Inhalation of fumes of the MR/liquid vaporizers may get entry into the brain by breaching the developing blood-brain barrier, hence deleterious to developing nervous system and can lead to long-term functional deficits. In the present study the consequence of MR exposure has further been investigated at various stages of development, evaluating free radical mediated effect pertinent to neurobehavioral and neurochemical functioning. Rat pups were exposed to pyrethroid-based MR (allethrin 3.6% w/v, 8 h/day through inhalation) during prenatal (GD1-20), postnatal (PND1-30) and perinatal (GD1-PND30) period of development and assessments were made on PND31. We observed significant oxidative stress, where an increase in lipid peroxidation and a decrease in antioxidants, glutathione, superoxide dismutase and catalase in various brain areas (cerebellum, corpus striatum, frontal cortex and hippocampus) were evident at all the exposure schedules. The hippocampus was the most affected region and further exhibited altered cholinergic functioning in the form of significant decrease in cholinergic (muscarinic) receptor binding (prenatal 32%, postnatal 35%, perinatal 38%) and inhibition in acetylcholinesterase activity (prenatal 20%, postnatal 31% and perinatal 33%). The neurochemical changes were found to accompany decrease in learning and memory performance in exposed rats, the function governed by hippocampus. The result suggests that pyrethroid-based MR inhalation during early developmental period may have adverse effect on developing nervous system causing cholinergic dysfunction leading to learning and memory deficit.
Sinha
Chaitali
C
Developmental Toxicology Division, Industrial Toxicology Research Centre, Post Box-80, M.G. Marg Lucknow 226001, India.
Seth
Kavita
K
Islam
Fakhrul
F
Chaturvedi
Rajnish Kumar
RK
Shukla
Shubha
S
Mathur
Neeraj
N
Srivastava
N
N
Agrawal
Ashok Kumar
AK
D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D001362:Avoidance Learning / Q000187:drug effects; D001522:Behavior, Animal / Q000187:drug effects*; D001724:Birth Weight / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects*; D002374:Catalase / Q000378:metabolism; D002490:Central Nervous System / Q000187:drug effects / Q000196:embryology / Q000254:growth & development*; D005260:Female; D005978:Glutathione / Q000378:metabolism; D007302:Insect Repellents / Q000633:toxicity*; D007306:Insecticides / Q000633:toxicity*; D007859:Learning Disabilities / Q000139:chemically induced / Q000523:psychology; D015227:Lipid Peroxidation / Q000187:drug effects; D008098:Litter Size / Q000187:drug effects; D008569:Memory Disorders / Q000139:chemically induced / Q000523:psychology; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects; D011247:Pregnancy; D011722:Pyrethrins / Q000633:toxicity*; D011869:Radioligand Assay; D051381:Rats; D017208:Rats, Wistar; D013482:Superoxide Dismutase / Q000378:metabolism
D007302:Insect Repellents; D007306:Insecticides; D011722:Pyrethrins; D002374:Catalase; D013482:Superoxide Dismutase; D000110:Acetylcholinesterase; D005978:Glutathione