Adverse ventricular-ventricular interactions in right ventricular pressure load: Insights from pediatric pulmonary hypertension versus pulmonary stenosis

Infants with congenital diaphragmatic hernia (CDH) fail to adapt at birth because of persistent pulmonary hypertension (PH), a condition characterized by excessive muscularization and abnormal vasoreactivity of pulmonary vessels. Activation of soluble guanylate cyclase by BAY 41-2272 prevents pulmonary vascular remodeling in neonatal rats with hypoxia-induced PH. By analogy, we hypothesized that prenatal administration of BAY 41-2272 would improve features of PH in the rabbit CDH model. Rabbit fetuses with surgically induced CDH at day 23 of gestation were randomized at day 28 for an intratracheal injection of BAY 41-2272 or vehicle. After term delivery (day 31), lung mechanics, right ventricular pressure, and serum NH2-terminal-pro-brain natriuretic peptide (NT-proBNP) levels were measured. After euthanasia, lungs were processed for biological or histological analyses. Compared with untouched fetuses, the surgical creation of CDH reduced the lung-to-body weight ratio, increased mean terminal bronchial density, and impaired lung mechanics. Typical characteristics of PH were found in the hypoplastic lungs, including increased right ventricular pressure, higher serum NT-proBNP levels, thickened adventitial and medial layers of pulmonary arteries, reduced capillary density, and lower levels of endothelial nitric oxide synthase. A single antenatal instillation of BAY 41-2272 reduced mean right ventricular pressure and medial thickness of small resistive arteries in CDH fetuses. Capillary density, endothelial cell proliferation, and transcripts of endothelial nitric oxide synthase increased, whereas airway morphometry, lung growth, and mechanics remained unchanged. These results suggest that pharmacological activation of soluble guanylate cyclase may provide a new approach to the prenatal treatment of PH associated with CDH.

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Apelin decreases myocardial injury and improves right ventricular function in monocrotaline-induced pulmonary hypertension

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00089.2009 ◽

2009 ◽

Vol 296 (6) ◽

pp. H2007-H2014 ◽

Cited By ~ 99

Author(s):

Inês Falcão-Pires ◽

Nádia Gonçalves ◽

Tiago Henriques-Coelho ◽

Daniel Moreira-Gonçalves ◽

Roberto Roncon-Albuquerque ◽

...

Keyword(s):

Pulmonary Hypertension ◽

Right Ventricular ◽

Systolic Pressure ◽

Pressure Rise ◽

Chronic Administration ◽

Left Ventricular ◽

Ventricular Pressure ◽

Peak Rate ◽

Male Wistar Rats ◽

Neurohumoral Activation

We investigated the endogenous production of apelin and the cardiac and pulmonary effects of its chronic administration in monocrotaline (MCT)-induced pulmonary hypertension (PH). Male Wistar rats were injected with MCT (60 mg/kg sc) or vehicle ( day 0). One week later, these animals were randomly treated during 17 days with pyroglutamylated apelin-13 (Pyr-AP13; 200 μg·kg−1·day−1 ip) or a similar volume of saline, resulting in four groups: sham ( n = 11), sham-AP ( n = 11), MCT ( n = 16), and MCT-AP ( n = 13). On day 25, right ventricular (RV) and left ventricular (LV) hemodynamic and morphometric parameters were assessed. Tissue and plasma samples were collected for histological and molecular analysis. When compared with sham, the MCT group presented a significant increase of RV mass (166 ± 38%), diameter of cardiomyocyte (40 ± 10%), myocardial fibrosis (95 ± 20%), peak systolic pressure (99 ± 22%), peak rate of ventricular pressure rise (dP/d tmax; 74 ± 24%), peak rate of ventricular pressure decline (dP/d tmin; 73 ± 19%), and time constant τ (55 ± 16%). In these animals, RV expression of apelin (−73 ± 10%) and its receptor APJ (−61 ± 20%) was downregulated, whereas mRNA expression of type B natriuretic peptide (9,606 ± 713%), angiotensinogen (191 ± 147%), endothelin-1 (RV, 497 ± 156%; and LV, 799 ± 309%), plasmatic levels of apelin (104 ± 48%), and angiotensin 1-7 (161 ± 151%) were increased. Chronic treatment with Pyr-AP13 significantly attenuated or normalized these changes, preventing apelin-APJ mRNA downregulation and PH-induced neurohumoral activation of several vasoconstrictors, which exacerbates apelin-APJ vasodilator effects. Therefore, apelin delayed the progression of RV hypertrophy and diastolic dysfunction. Together, these observations suggest that the apelin-APJ system may play an important role in the pathophysiology of PH, representing a potential therapeutic target since it significantly attenuates RV overload and PH-induced neurohumoral activation.

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Rosuvastatin, Sildenafil and Their Combination in Monocrotaline-Induced Pulmonary Hypertension in Rat

Acta Pharmaceutica ◽

10.2478/acph-2014-0029 ◽

2014 ◽

Vol 64 (3) ◽

pp. 345-353 ◽

Cited By ~ 6

Author(s):

Magdalena Jasińska-Stroschein ◽

Jacek Owczarek ◽

Anna Wesołowska ◽

Daria Orszulak-Michalak

Keyword(s):

Pulmonary Hypertension ◽

Right Ventricle ◽

Right Ventricular ◽

Density Lipoprotein ◽

Ventricular Pressure ◽

Positive Role ◽

Phosphodiesterase Type 5 Inhibitor ◽

Hypertension Development ◽

Experimental Findings ◽

Hydrophilic Statin

Abstract There is considerable interest in the pleiotropic effects of statins and their potential role in the treatment of pulmonary hypertension. Previous experimental findings indicate that a combination of lipophilic statins with phosphodiesterase type-5 inhibitor, sildenafil, can offer preventive effects on rat monocrotaline-induced pulmonary hypertension. The present study is aimed to assess whether therapeutic regimen provides any benefits. Seven days after pulmonary hypertension induction, hydrophilic rosuvastatin and sildenafil were given for 14 days to male Wistar outbred rats. Right ventricular pressure, right ventricle mass and three biomarkers were evaluated after 21 days: brain natriuretic peptide, high-density lipoprotein cholesterol and vascular endothelial growth factor. The present study demonstrates that administration of hydrophilic statin with sildenafil results in reduction of pulmonary vascular remodeling and right ventricular pressure. The results of biochemical measurements may suggest that statins play a positive role in right ventricle function or the process of angiogenesis in pulmonary hypertension development.

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