strain: Otsuka Long-Evans Tokushima Fatty (OLETF) rats gender: male age: 55 weeks tissue: liver intervention: 0.2% thiamine containing water free access for 51 weeks
Treatment protocol
The animal protocols were approved by the Institutional Animal Care and Use Committee of Osaka University of Pharmaceutical Sciences. Otsuka Long-Evans Tokushima Fatty (OLETF) male rats at 4 weeks of age were kindly supplied by the Tokushima Research Institute, Otsuka Pharmaceutical (Tokushima, Japan). OLETF rats were randomly divided into 2 groups of 8 each: untreated control and thiamine-treated animals. The latter group received 2 g thiamine/L in their drinking water. Rats were housed in standard cages (2 rats per cage) with free access to water and standard chow, unless noted otherwise. Cages were kept in temperature-controlled animal quarters (21°C) with a 0600-1800 light: 1800-0600 dark cycle, which was maintained throughout the experimental period. All animals were provided standard rodent chow (NMF, Oriental Yeast Co., Tokyo, Japan). Cages were changed at the beginning of each week and body weights were measured between 0800 and 1000. Body weight, food, and water intake were measured weekly throughout the investigation. The control and treated rats were sacrificed at 55 weeks of age (thiamine treatments for 51 weeks; n = 8 per group). After 16 h of fasting, a rat was anesthetized with pentobarbital (50 mg/Kg), and an indwelling catheter was inserted in the right carotid artery. From exsanguinated animals, samples of liver were removed, and rinsed in ice-cold saline. Parts of liver were placed in RNAlater® (Ambion, Austin, TX) and stored at -80ºC, until further analysis. Individual samples were run on separate microarrays (n = 2, for both thiamine-treated and control groups); no samples were pooled.