**2. Materials and Methods**

#### *2.1. Animals*

The Institutional Review Board of Kyungpook National University approved the care and use of animals (approval No. 2021-0192). Every effort was made to minimize both the number of animals used and their suffering. Seven-week-old male SS rats (DIS/EisSlc; Dahl-Iwai S) and SR rats (DIR/EisSlc; Dahl-Iwai R) were purchased from Japan SLC, Inc. (Hamamatsu, Shizoka, Japan, n = 6). The rats were acclimatized for a couple of weeks before being randomly assigned into one of two groups fed with a chow diet (CD; containing 8.6% fat; SAFE, Paris, France) [20] or a HFD (60% fat, Research Diets, Inc., New Brunswick, NJ, USA) and allowed free access to food and tap water for 12 weeks. The body weight of the rats was monitored weekly for 12 weeks using an electronic scale (KB-5000, A&D KOREA Ltd., Seoul, Korea). Caloric intake was calculated by multiplying food intake (g/day) by 3.1 kcal/g for the CD groups and 5.2 kcal/g for the HFD groups, respectively. The rats were anesthetized with sodium pentobarbital (50 mg/kg intraperitoneally) for sacrifice, after which, tissues were obtained, frozen in liquid nitrogen, and stored at −80 ◦C until further study.
