Bioallethrin causes permanent changes in behavioural and muscarinic acetylcholine receptor variables in adult mice exposed neonatally to DDT.

We recently reported changes in the density of muscarinic acetylcholine receptors in cerebral cortex of mice treated neonatally with DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)-ethane) and receiving bioallethrin as adults. We also found behavioural aberrations in adult mice treated with bioallethrin, whether neonatally treated with DDT or the vehicle. To ascertain whether these changes were permanent, 10-day-old mice received an oral dose of DDT (0.5 mg/kg body weight) and at the age of 5 months they received bioallethrin orally (0.7 mg/kg body weight/day; 7 days). The animals were investigated at the age of 7 months. Here we report muscarinic acetylcholine receptor changes, additional behavioural disturbances and learning disabilities in mice receiving DDT as neonates and bioallethrin as adults, whereas the behavioural disturbances in mice receiving vehicle as neonates and bioallethrin as adults had diminished and changes in proportions of high- and low-affinity binding sites had developed. No changes in the density of nicotinic acetylcholine receptors were noted for any of the treated groups. In conclusion, exposure of neonates to DDT leads to increased susceptibility in adults to a short-acting pesticide with similar neurotoxic action. An adult exposure to this short-acting pesticide to mice neonatally exposed to DDT leads to irreversible muscarinic acetylcholine receptor changes and behavioural disturbances with additional changes 2 months after the exposure.