Impact of dimethoate on brain of the earthworm Eudicho gaster kinneari (Stephenson): A histological profile

Adult Eudichogaster kinneari were exposed to a safe concentration (0.6 ppm) of Dimethoate for twenty days to evaluate the effects on histoarchitecture of cerebral and sub pharyngeal ganglion of brain. Brain was severely affected with exposure of above insecticide, causing degeneration of neurosecretory cells (NSCs). Initially neurosecretory cells exhibited accelerated neurosecretory activity while repeated treatment led exhaustion of neurosecretory material (NSM). The neurosecretory cells lost their normal shape along with many morphological alterations, vacuolization were seen in cytoplasm, nucleoplasm, neurosecretory material and in neuropile, ultimately caused imbalance and lethal effect. Size enhancement in cell area, nuclear diameter, cell length and axon length of neurosecretory cells (p>0.001) were observed significantly.