Animal Model of PAH
All protocols had been approved by the animal research committee of
Kaohsiung Medical University (IACUC approval NO: 104226). Male Wistar
rats weighing approximately 220 g were purchased from National Animal
Center, Taiwan. after arriving at the Kaohsiung Medical University
vivarium, the rats were acclimated for at least one week before being
used in the experiment. They were housed in a room on a 12-hr light/dark
cycle under controlled temperature of 22.1℃ and relative humidity of
55%, and they were provided with normal chow and water ad libitum. On
the day of experiment, animals were anesthetized with a mixture of
sodium pentobarbitone (20 mg/kg, i.p.) and ketamine (40 mg/kg, i.m.)
under orotracheally ventilated rodent respirators (Harvard, South
Natick, MA) and lateral thoracotomy in the third intercostal space was
performed. Left lung of rats was resected and closed by clip ligation
(Ligaclip multiple clip applier, medium size, Ethicon Endo-Surgery), and
the animals were suture to prevent pneumothorax. The chest retractor was
then removed after 15 minutes, and the thymus was moved back to its
physiological position. The chest cavity and skin were closed. The
entire procedure took less than 30 min for each rat. After operation,
rats were extubated and received an additional injection of sterile
saline (10 ml). On the following day, SU5416 (25 mg/kg) was injected
subcutaneously in surviving rats. Sham-operated animals underwent
identical operation without pneumonectomy (PNx) and received sterile
saline (20 mg/kg) subcutaneously, instead. The day of SU5416 injection
was designated as day 0. All animals were individually housed in a 12-h
dark/light cycle-controlled room and fed a regular rat diet. The
procedure was also shown in supplemental figure 1.