[Changes on level and expression of endothelin-1 in the lungs of rats with hypoxic pulmonary hypertension].
The aim of the present study was to determine whether mRNA for endothelin-1 (ET-1) was present and changed in the lungs of rats exposed to chronic hypoxia, cRNA probes for rat ET-1 and c-fos were labelled by in vitro transcription with digoxigenin-UTP for in situ hybridization. Endothelin-1 like immunoactivity (ET-1-LI) in plasma as well as in lung homogenate was measured by radio-immunoassay. The results showed that the vascular endothelia cells of pulmonary artelics and the bronchiolar epithelial cells were strongly positive for the ET-1 probe. The perivascular and peribronchiolar smooth muscle were positive for the c-fos probe primarily. Whereas, there were little expression of ET-1 and c-fos in the rat lungs in controls. There were significant increase of ET-1-LI levels in rats exposed to hypoxia for 3 weeks, the concentration in venous samples was 3.85 +/- 1.52ng/L (P < 0.05 as compared with the control groups), in arterial sample was 4.72 +/- 1.66ng/L (P < 0.05) and in lung tissue was 2.06 +/- 0.68ng/g wet lung weight (P < 0.05). It is suggested that chronic hypoxia elevated the mean pulmonary arterial pressure, caused vessel remodelling and right ventricular hypertrophy. These changes were accompanied by an increase of ET-1 in plasma and lung homogenate. The expression and production of ET-1 were localized to endothelium and airway epithelium in the lungs.
Yang
X
X
Department of Internal Medicine, First University Hospital, West China University of Medical Sciences, Chengdu.
Chen
W
W
Chen
J
J
D000818:Animals; D019332:Endothelin-1 / Q000378:metabolism*; D006976:Hypertension, Pulmonary / Q000378:metabolism*; D000860:Hypoxia / Q000150:complications*; D008168:Lung / Q000378:metabolism*; D008297:Male; D016760:Proto-Oncogene Proteins c-fos / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017208:Rats, Wistar
D019332:Endothelin-1; D016760:Proto-Oncogene Proteins c-fos; D012333:RNA, Messenger