Thiodan stress on brain neurosecretory cells of the earthworm Eudichogaster kinneari: A Histological profile

Adult Eudichogaster kinneari were exposed to a safe concentration (0.003 ppm) of thiodan for twenty days to evaluate the effects on neurosecretory cells of cerebral and sub pharyngeal ganglion of brain. Brain was severely affected by exposure of above insecticide causing denatured neurosecretory cells due to vacuolization and liquification in cytoplasm, nucleoplasm, in neurosecretory material and in neuropile. Irregular shape of neurosecretory cells were seen, vizuneven stain, disorderly thickened and broken cell membrane was seen at many places. Most of the neurosecretory material became fragmented and accumulated around the nucleus. Ultimate atrophy of whole histological architecture of neurosecretory cells in both the ganglion of brain was seen. Significant reduction was observed in diameter of cell area, nuclear area, cell length and axon length of neurosecretory cells (p< 0.001).