NEUROTOXICOLOGICAL EFFECTS OF DELTAMETHRIN ON THE POSTNATAL-DEVELOPMENT OF CEREBELLUM OF RAT

Deltamethrin (DLT) has been accepted to be 10,000 times less toxic to man than to insects, While toxicity of DLT in adult animals has been s tudied using biochemical and electrophysiological tools, reports on it s developmental neurotoxicity are rather scanty, Wistar rat pups were exposed to DLT (0.7 mg/kg body wt/day, i.p., dissolved in propylene gl ycol) from postnatal day 9-13. Equal number of age matched pups were u sed as vehicle controls, The animals were weighed and perfused intraca rdially on postnatal days 12, 15, 21, and 30 and their brains dissecte d out. Cerebellum along with the brainstem was separated by a transver se section at the tectal level and processed for morphometric and toxi cological studies, The micro- and inter-neurons in the cerebellum are known to differentiate and mature, both morphologically and biochemica lly, during the postnatal life of rats. Postnatal exposure to DLT has been observed to delay the cytogenesis and morphogenesis of these neur ons. In addition to this, damage to the developing vasculature has als o been recorded in the form of thrombus and haemorrhage. Focal degener ation and spongy appearance of the tissue in the vicinity of the damag ed blood vessels have also been recorded, The study has opened up seve ral questions on the safety of this substance to the pregnant mothers and infants in the habitats where this substance is in use for vector control.