Spr 671

All animal experiments were performed in accordance with the protocols approved by the Committee of Experimental Animal Research of Gunma University (Permit Number; 11–027). Hypoxia-induced PH models were used to assess the development of PH in mice. Eight-week-old male wild-type (WT) mice on a normal chow diet were exposed to hypoxia (10% O₂) or normoxia for 4 weeks as previously described[19 (link),20 (link)]. Briefly, hypoxic mice were housed in an acrylic chamber with a nonrecirculating gas mixture of 10% O₂ and 90% N₂ by adsorption-type oxygen concentrator to utilized exhaust air (Teijin, Tokyo, Japan), whereas normoxic mice were housed in room air (21% O₂) under a 12-hour light/dark cycle. After 4 weeks of exposure to hypoxia (10% O₂) or normoxia, mice were anesthetized with isoflurane (1.0%). To examine the development of PH, we measured right ventricular systolic pressure (RVSP), right ventricular hypertrophy (RVH), and pulmonary vascular remodeling. For right heart catheterization, a 1.4-F pressure catheter (SPR-671, Millar Instruments Inc,USA) was inserted in the right jugular vein and advanced into the RV to measure RVSP as described previously[21 (link)]. All data were analyzed using the PowerLab data acquisition system (AD Instruments, Australia) and averaged >10 sequential beats.

A 1.4 French micro-manometer-tipped catheter (SPR-671; Millar Instruments Inc.) was inserted into the right carotid artery and advanced into the LV of mice that were lightly anesthetized (i.e., maintained spontaneous respirations) with tribromoethanol/amylene hydrate (2.5% w/v, 8 μL/g, injected intraperitoneally; Avertin) For in vivo hemodynamic measurements. Hemodynamic parameters, including heart rate, LV end-diastolic pressure, +dP/dt, and −dP/dt were recorded in closed-chest mode at baseline and in response to 10 ng isoproterenol administered via cannulation of the right internal jugular vein [28 (link)].