Fluoride Action Network


Effects of fluoride (F) on lipid peroxidation and enzyme activity levels in the hippocampus and neocortex were studied in 6- to 7-week-old female Wistar rats in five groups of six administered intraperitoneal doses of NaF in physiological saline over the range of 0, 1, 5, 10, and 20 mg NaF/kg bw/day for 14 days. Body weight and brain index decreased significantly (p <0.05) as F levels increased in the hippocampus and neocortex. Activities of the free radical enzymes superoxide dismutase (SOD), glutathione S-transferase (GST) and catalase (CAT) likewise decreased significantly (p<0.05), whereas the level of lipid peroxidation (LPO) and the activities of glutathione peroxidase (GPX) and xanthine oxidase (XOD) increased compared with those of the control group. The enzymes of secondary signaling, protein kinase C (PKC) and neuronal nitric oxide synthase (nNOS), also increased compared with the control. Dopamine, serotonin, 5-hydroxyindoleacetic acid and homovanillic acid levels likewise increased, whereas norepinephrine and epinephrine levels decreased. The NaF administered groups showed dose-dependent responses with more significant effects in the two higher dosage groups. Although NaF treatment produced significant neurochemical alterations in both the hippocampus and neocortex, there was not much difference in the degree of effects in the two organs.