Coda tail cuff blood pressure monitoring system

All experiments were performed in accordance with the appropriate Home Office project licence and complied with the UK Animal (Scientific Procedures) Act 1986. Male C57BL/6j mice were randomly assigned to three groups; control, obese, and exercised obese (see below) and aged until 18–20 weeks. Animals were housed under a 12-h light/12-h dark cycle and provided with food and water ad libitum. The body weights of all groups were recorded every 2 weeks from 8 weeks of age. Mice were fasted overnight and sacrificed using CO₂ asphyxiation. Prior to sacrifice, blood pressure was recorded in conscious, restrained animals using the CODA tail cuff blood pressure monitoring system (Kent Scientific, USA). Immediately after sacrifice mixed blood samples were collected by severing the thoracic aorta. Blood glucose concentration was measured immediately using an automatic blood glucose system (Contour, Bayer Consumer Care AG, Basel, Switzerland). Following euthanisation, the mesentery was exposed and removed. Epididymal fat pads, hearts, and kidneys were collected and weighed.

Body composition of fat and lean mass was measured by nuclear magnetic resonance (NMR) spectroscopy (Bruker Minispec LF90II, Bruker, Billerica, USA) as previously reported and normalized to total body weight (28 (link)). The volume of oxygen consumption (VO₂), carbon dioxide production (VCO₂), spontaneous motor activity and food intake were measured using the Comprehensive Laboratory Monitoring System (CLAMS) (Columbus Instruments, Columbus, USA) (28 (link)). The respiratory exchange ratio (RER) was calculated from the ratio of VCO₂ to VO₂. Mice were individually placed into the sealed chambers with free access to food and water. The study was carried out in a room set at 22^oC with 12-12 hr (6:00 am ~ 6:00 pm) light-dark cycles, and the measurements were carried out continuously for 72 hours after a 24 h acclimatization period. The data were averaged over 72 hr. Rectal body temperatures were measured by a BAT-12 thermometer (Physitemp, USA). Blood pressure was recorded in conscious, restrained mice at age of 7 weeks and 14 weeks using the CODA tail cuff blood pressure monitoring system (Kent Scientific, USA).