VEGFmRNA and eNOSmRNA expression in immature rabbits with bleomycin-induced pulmonary hypertension.
OBJECTIVE
To investigate the evolution of pulmonary hypertension, the pathological changes of pulmonary arteries, and the expression of VEGFmRNA and eNOSmRNA of pulmonary arterial endothelial cells in immature rabbits treated with intratracheal bleomycin (BLM).


METHODS
Immature rabbits were divided into control and BLM group. Two and four weeks after intratracheal normal saline or BLM injection, the systolic, diastolic and mean pulmonary artery pressure (PASP, PADP, MPAP) were measured by micro-catheter; the pathological changes and the expression of VEGFmRNA and eNOSmRNA of endothelial cells in pulmonary arteries were evaluated by HE and in situ hybridization.


RESULTS
Two and four weeks after intratracheal injection of BLM, the PASP, PADP and MPAP increased 53%, 49%, 52% in 2 weeks, and 43%, 89%, 56% in 4 weeks; the wall thickness increased and the cavity in middle and small pulmonary arteries became narrow; the Thickness Index (TI) and Area Index (AI) increased 25%, 14% in 2 weeks, and 22%, 24% in 4 weeks; the level of VEGFmRNA and eNOSmRNA expression decreased 46%, 43% in 2 weeks, and 43%, 51% in 4 weeks. There was no significant difference between 2 weeks and 4 weeks BLM groups.


CONCLUSIONS
The pulmonary artery pressure was elevated, the thickness of wall increased and the cavity became narrow in middle and small pulmonary arteries, and the level of VEGFmRNA and eNOSmRNA expression in pulmonary arterial endothelial cells decreased in immature rabbits after 2 weeks and 4 weeks of intratracheal 4 U/kg BLM injection.
Gong
Fang-Qi
FQ
Affiliated Children's Hospital, College of Medicine, Zhejiang University, Hangzhou 310003, China. gongfangqi@zju.edu.cn
Lin
You-Min
YM
Tang
Hong-Feng
HF
Gu
Wei-Zhong
WZ
Wang
Wei
W
Kang
Man-Li
ML
D000818:Animals; D001761:Bleomycin / Q000633:toxicity*; D001835:Body Weight / Q000187:drug effects; D006976:Hypertension, Pulmonary / Q000378:metabolism* / Q000473:pathology; D019001:Nitric Oxide Synthase / Q000235:genetics*; D052250:Nitric Oxide Synthase Type III; D011651:Pulmonary Artery / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000032:analysis*; D011817:Rabbits; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics*
D012333:RNA, Messenger; D042461:Vascular Endothelial Growth Factor A; D001761:Bleomycin; D019001:Nitric Oxide Synthase; D052250:Nitric Oxide Synthase Type III