Ali Abbaszadeh-cheragheali - Student Research Committee, Torbat Heydariyeh University of Medical Sciences, Torbat Heydariyeh, Iran
Farimah Beheshti - Neurocognitive Research Center, School of Medicine, Mashhad University of Medical Sciences, Iran
Sareh Karimi - Neurocognitive Research Center, School of Medicine, Mashhad University of Medical Sciences, Iran
Farzaneh Vafaee - Neurogenic Inflammation Research Center, School of Medicine, Mashhad University of Medical Sciences, Iran
Mohammad Naser Shafei - Neurocognitive Research Center, School of Medicine, Mashhad University of Medical Sciences, Iran
Hamid Reza Sadeghnia - Pharmacological Research Center of Medicinal Plants, School of Medicine, Mashhad, University of Medical Sciences, Mashhad, Iran

Introduction & Objective: In this study effects of Vitamin C (Vit C) on hypothyroidism-associated learning and memory impairment during neonatal and juvenile growth in rats was investigated.Method: Fifteen pregnant rats were kept in separate cages and after delivery randomly divided into five groups and treated as follows: (۱) Control (normal drinking water); (۲) propylthiouracil (PTU ۰.۰۰۵%); (۳-۵) PTU-Vit C ۱۰, ۱۰۰ & ۵۰۰ received PTU ۰.۰۰۵% and ۱۰, ۱۰۰ and ۵۰۰ mg/kg Vit C from the first day after birth through the first ۸ weeks of life of offspring. ۱۰ male offsprings of each group were randomly selected and tested in the Morris water maze (MWM) and passive avoidance (PA). Brains were removed for biochemical measurements.Results: PTU increased time latency and reduced time spent in target quadrant in MWM and decreased latency for entering to the dark compartment in PA. PTU reduced serum thyroxine and thiol groups, superoxide dismutase (SOD) and catalase (CAT) activities in brain and increased hippocampal molondialdehyde (MDA). In MWM test, ۱۰۰ and ۵۰۰ mg/kg Vit C reduced time latency and traveled distance and all doses of Vit C increased the spent time and traveled distance in target quadrant, while increased the time latency for entering to the dark compartment in PA. Vit C increased serum thyroxine, thiol, SOD and CAT in the brain tissues while reduced MDA.conclusion: Results demonstrated Vit C has protective effects on hypothyroidism-associated learning and memory impairment during neonatal and juvenile growth in rats that it might be due to the antioxidative effects of Vit C.

Vitamin C, Hypothyroidism, Memory, Oxidative stress