Tail cuff plethysmography

Male fourteen-week-old WKY (Mean SBP: 132 ± 6 mmHg) and SHR (Mean SBP: 209 ± 5 mmHg) from Charles River were acclimated to housing conditions for 2 weeks. Systolic blood pressure (SBP) was measured by Tail-Cuff Plethysmography (Visitech Systems) with the plate temperature set at 35 °C. All studies were approved by the Institutional Animal Care and Use Committee of the University of Florida. Rats were maintained in accordance with the Animal Welfare Act and the Public Health Policy on Humane Care.

Male 8 to 10-week-old male C57/B6 mice were purchased from the Shanghai Experimental Animal Center, China. The investigation conforms with the Guide for the Care and Use of Laboratory Animals published by the United States National Institutes of Health (NIH Publication No. 85-23, revised 1996) and was approved by the Ethics Review Board of Ruijin Hospital, Shanghai, China. Four groups of animals were included: vehicle infusion (0.9% NaCl solution, control), vehicle infusion+EMD638683, AngII infusion, Ang II infusion+EMD638683. Ang II (1000 ng/kg/min) was infused for 2 weeks using Alzet mini-osmotic pumps (model 1002, DURECT, Cupertino, CA, United States) implanted subcutaneously in the surgery. EMD638383 was delivered i.p daily at a dosage of 10 mg/kg body weight. Systolic blood pressure was measured on every week by tail-cuff plethysmography (Visitech Systems, Apex, NC, United States) as a control for efficient AngII infusion. All surgical procedures were practiced under anesthesia.

The blood pressure was measured by tail-cuff plethysmography (Visitech Systems, USA) every 2 days during E1.5–7.5 and then every day during E7.5–17.5. The mice were maintained conscious and in restraints, and 10–20 actual measurements were obtained after normalization.