Local and Peripheral Plasma Endothelin-1 in Pulmonary Hypertension Secondary to Chronic Obstructive Pulmonary Disease

Abstract

Endothelin-1 (ET-1) has been described to have crucial effects in the initiation and evolution of pulmonary hypertension (PH) secondary to cardiac disorders. However, the precise role of ET-1 in PH induced by chronic obstructive pulmonary disease (COPD) is not yet clear. The objective of this cross-sectional study was to determine the local and peripheral plasma ET-1 profile of COPD patients with or without PH. Twenty-six COPD patients with clinical and/or laboratory findings suspicious of PH, and 20 healthy smoker volunteers constituted the study population. Patients were allocated to PH (n = 17) and non-PH (n = 9) groups according to their pulmonary artery pressures determined by right-heart catheterization. Plasma ET-1 samples, obtained from the main pulmonary artery (mixed venous blood) and peripheral blood (radial artery and brachial vein), were assessed by radioimmunoassay. Brachial vein ET-1 levels were within normal ranges in PH (2.7 ± 0.5 pg/ml) and non-PH (3.2 ± 0.7 pg/ml) COPD patients compared with that of the controls (4.4 ± 0.1 pg/ml). Likewise, radial artery ET-1 levels in PH (3.3 ± 0.7 pg/ml) and non-PH (2.9 ± 0.8 pg/ml) groups, and in controls (3.4 ± 1.1 pg/ml) were also comparable. The pulmonary artery ET-1 concentration of the PH group (13.6 ± 3.7 pg/ml) was higher than that of the non-PH group (2.2 ± 0.4 pg/ml) and that of the peripheral blood levels of controls. Elevated pulmonary artery ET-1 in the PH group was inversely correlated only with PaO₂ levels. These results could be taken as an evidence of a local role of ET-1 in COPD-induced PH, but it remains to be clarified whether ET-1 is a marker or a mediator of PH in COPD.

Lung-Heart Clinical Crosstalk in the Course of Copd Exacerbation

“…Left heart insufficiency, one of the major causes of secondary PHT [10], was not a reason for PHT in our study (Table 4) as the LVEF was within normal range in most patients in the studied group [12]. The results www.pneumonologia.viamedica.pl are not in agreement with Stolz et al [36], who revealed that BNP levels are elevated during COPD exacerbation. This discrepancy might be explained by the fact that in the study by Stolz et al [37] blood was collected directly on admission and again at follow-up after hospitalisation.…”

Thymoquinone-induced relaxation of isolated rat pulmonary artery

“…Moreover, patients with pulmonary hypertension (PH) have increased expression of ET-1 and its mRNA in endothelial cells of the pulmonary vasculature (Cacoub et al, 1997). Increased pulmonary artery ET-1 levels were also reported in chronic obstructive pulmonary disease (COPD) patients with PH, but not in those who did not develop PH (Celik and Karabiyikoglu, 1998). The role of endogenous ET-1 in human PH has also been demonstrated by prevention, reversal or blunting of PH development in rats treated with endothelin receptor antagonists specially ET A receptor subtype.…”

Genistein, a Phytoestrogen, Attenuates Monocrotaline-Induced Pulmonary Hypertension

“…Peptide levels of ET-1 have been reported to be increased in pulmonary artery of chronic obstructive pulmonary disease complicated by PH but not chronic obstructive pulmonary disease alone [38]. MCT-induced PH increased plasma ET-1 levels and exhibited various alterations of ET-1 expression in lungs [18,19,20,21,22,23,24,25].…”