RESUMO
To observe the changes of endothelin(ET) and atrial natriuretic peptide(ANP) lev-els in chronic hypoxic pulmonary hypertensive rats and discuss their mechanism. Methods: We duplicatedthe models of chronic hyp0xic pulmonary hypertensive rats and tested the concentrations of ET and ANP ofplasma and cardiac tissue by radioimmunoassey. Results: In pulmonary hypertension group, plasma ET,plasma ANP and myocardial ET levels increased more significantly than those of controls,except that my-ocardial ANP concentration decreased. There were positive c0rrelati0ns between plasma ET level and plas-ma ANP level and between plasma ET level and myocardial ET level, but a negative correlation betweenplasma ANP level and myocardial ANP level. C0nclusion: It is suggested that the synthesis and secretionof ET and ANP increase in pulmonary hypertension,and therefore provides reference to clinical diagnosisand therapy.