Histological changes in the brain of young fluoride-intoxicated rats

Wistar albino rats were exposed to 30 or 100 ppm fluoride (as NaF) in drinking water during their fetal, weanling, and post-weaning stages until the age of ten weeks. Rats exposed to 30 ppm fluoride did not show any notable alterations in brain histology, whereas rats exposed to 100 ppm fluoride showed significant neurodegenerative changes in the hippocampus, amygdala, motor cortex, and cerebellum. Changes included decreases in size and number of neurons in all the regions, decrease in the number of Purkinje cells in the cerebellum, and signs of chromatolysis and gliosis in the motor cortex. These histological changes suggest a toxic effect of high-fluoride intake during the early developing stages of life on the growth, differentiation, and subcellular organization of brain cells in rats.