Characterization of Pde9a-deficient Mice

Animal studies were conducted at Sanford Burnham Prebys Medical Discovery Institute (SBP), Vanderbilt University Medical Center (VUMC), and Johns Hopkins University and School of Medicine (JHSOM). Pde9a^−/− mice on a C57BL/6J background were previously described (37 (link)). Mice were maintained on a 12-h light/dark cycle with two to five animals per cage and ad libitum food and water. At 6 weeks of age, SBP and VUMC mice received nutrient-matched Surwit diets: a control low-fat diet (LFD) (10.5% calories from fat: D12328; Research Diets) or high-fat diet (HFD) (58.0% calories from fat: D12330; Research Diets). JHSOM mice were fed HFD (60.0% calories from fat: D12492; Research Diets). Mice were weighed twice weekly, and body composition was measured using a Minispec Body Composition Analyzer (Bruker) at SBP and Vanderbilt Mouse Metabolic Phenotyping Center (VMMPC) or EchoMRI-100 (Echo Medical Systems) at JHSOM. Mice were fasted for 5-h prior to euthanasia by CO₂ asphyxiation and exsanguination via cardiac puncture. All procedures were approved by the Institutional Animal Care and Use Committees at SBP, VUMC, and JHSOM.