Chronic hypoxic pulmonary hypertension (PH), associated with increased pulmonary arterial pressure (PPA) and right ventricular hypertrophy (RVH), correlates significantly with calcitonin gene-related peptide (CGRP) and somatostatin (SOM) levels in lung and blood.
Rats injected with interleukin-1 (10 micrograms) and tumor necrosis factor (10 micrograms) and then exposed continuously to hyperoxia (greater than 99% O2, 1 atm) survived longer, had increased lung reduced/oxidized glutathione ratios, smaller pleural effusions, less pulmonary hypertension and improved arterial blood gases.
To explain the increase in potency it is speculated that during the development of pulmonary hypertension the mechanism whereby ET-1 and NA contract pulmonary arteries may change from one in which Ca2+ influx plays only a minor role to one in which Ca2+ influx predominates, although no direct evidence to support this speculation has yet been obtained.
Our results support the hypothesis that the 5-LO is involved in lung vascular tone regulation and in the development of chronic pulmonary hypertension in hypoxic rodent models.
These results indicate that chronic fenfluramine exposure potentiates the pulmonary vasoconstrictor response to ET-1, and suggests that elevated levels of serotonin may <prime> the pulmonary circulation to become hyperreactive to other vasoactive substances possibly leading to the development of disease states such as primary pulmonary hypertension.
These data show that, in rats, the increased 5-HTT expression that follows dexfenfluramine discontinuation promotes the development of hypoxic pulmonary hypertension.
The increased incidence of the disease in young women, the familial cases, the association with autoimmune disorders, and the recent discovery that mutation of the PPH1 gene may not be restricted to familial PPH support the hypothesis that the development of pulmonary hypertension likely implies an individual susceptibility or predisposition, which is probably genetically determined.
Other characteristics of patients presenting with severe PH were poor compliance to ERT (4/9 patients) or no ERT (5/9 patients), a family history of a sib with GD and PH (2/2 patients), an excess of ACE I allele (OR 2.3, 95% CI 1.1-4.9, P=0.034) and an excess of non-N370S GBA mutation (OR 6.0, 95% CI 1.1-33, P=0.003).
Other characteristics of patients presenting with severe PH were poor compliance to ERT (4/9 patients) or no ERT (5/9 patients), a family history of a sib with GD and PH (2/2 patients), an excess of ACE I allele (OR 2.3, 95% CI 1.1-4.9, P=0.034) and an excess of non-N370S GBA mutation (OR 6.0, 95% CI 1.1-33, P=0.003).
Finally, we suggest that these observations may help to explain why patients with pulmonary hypertension experience exacerbations after taking indomethacin and that the newly introduced selective cyclooxygenase-2 inhibitors may increase endothelin-1 production in susceptible patients, leading to vascular remodeling and the development of pulmonary hypertension.
Finally, we suggest that these observations may help to explain why patients with pulmonary hypertension experience exacerbations after taking indomethacin and that the newly introduced selective cyclooxygenase-2 inhibitors may increase endothelin-1 production in susceptible patients, leading to vascular remodeling and the development of pulmonary hypertension.
Increased expression of the cGMP-inhibited cAMP-specific (PDE3) and cGMP binding cGMP-specific (PDE5) phosphodiesterases in models of pulmonary hypertension.