title: Vitamin C reverses lead-induced deficits in hippocampal synaptic plasticity in rats.
abstract: Lead (Pb) is a neurotoxic metal that is widely distributed in the environment. In experimental animals, chronic exposure to this neurotoxicant resulted in impaired synaptic plasticity and cognitive function. In this study, we examined the protective effects of vitamin C (ascorbic acid) against Pb exposure-induced impairment of long-term potentiation (LTP). Forty-four adult male Wistar rats were divided into six groups and subjected to the following treatments for three months: (1) vehicle (distilled water); (2) Pb; (3) ascorbic acid; (4) Pb+ascorbic acid; (5) Pb (two months) followed by ascorbic acid; and (6) ascorbic acid (one month) followed by Pb. After treatment, the population spike (PS) amplitude and slope of excitatory postsynaptic potentials (EPSP) were measured in the dentate gyrus(DG) of rats in vivo. Following these measurements, blood samples were collected for the following biochemical assays: malondialdehyde (MDA), total antioxidant capacity (TAC), and total oxidant status (TOS). There was a significant increase in plasma MDA and TOS in the Pb-intoxicated group compared to the control group. There was a significant increase in TAC levels in the ascorbic acid group. Our results also show that Pb exposure caused a decrease in the EPSP slope and PS amplitude when compared with the control group, whereas vitamin C increased these parameters. Co-administration of Pb with vitamin C inhibited the effects of Pb. These findings suggested that Pb exposure caused impairment in LTP, that may have been mediated through oxidative damage. Vitamin C ameliorated the Pb-induced impairment of synaptic plasticity in the DG via antioxidant activity.
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Ruhollah
authors.initials: R
authors.lastname: Karamian
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran. Electronic address: alirezakomaki@gmail.com.
authors.forename: Alireza
authors.initials: A
authors.lastname: Komaki
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Iraj
authors.initials: I
authors.lastname: Salehi
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Lida
authors.initials: L
authors.lastname: Tahmasebi
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Komaki
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Siamak
authors.initials: S
authors.lastname: Shahidi
authors.affiliation: Neurophysiology Research Center, Hamadan University of Medical Sciences, Hamadan, Iran.
authors.forename: Abdolrahman
authors.initials: A
authors.lastname: Sarihi
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology*; D003072:Cognition Disorders / Q000503:physiopathology / Q000517:prevention & control; D018891:Dentate Gyrus / Q000187:drug effects* / Q000503:physiopathology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D009473:Neuronal Plasticity / Q000187:drug effects* / Q000502:physiology; D018696:Neuroprotective Agents / Q000494:pharmacology*; D009942:Organometallic Compounds / Q000633:toxicity*; D018384:Oxidative Stress / Q000187:drug effects / Q000502:physiology; D011897:Random Allocation; D017208:Rats, Wistar
chemical_list: D000975:Antioxidants; D018696:Neuroprotective Agents; D009942:Organometallic Compounds; D008315:Malondialdehyde; D001205:Ascorbic Acid; C008261:lead acetate
keywords: Antioxidant; Dentate gyrus; Lead acetate; Long-term potentiation; Synaptic plasticity; Vitamin C