Sildenafil improves the beneficial hemodynamic effects exerted by atorvastatin during acute pulmonary thromboembolism.

Department of Pharmacology, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Brazil.
European journal of pharmacology (Impact Factor: 2.59). 09/2011; 670(2-3):554-60. DOI: 10.1016/j.ejphar.2011.09.018
Source: PubMed

ABSTRACT We investigated whether atorvastatin has beneficial hemodynamic effects during acute pulmonary thromboembolism (APT) and whether sildenafil improves these effects. We studied the involvement of oxidative stress, matrix metalloproteinases (MMPs), and neutrophil activation. APT was induced with autologous blood clots (500 mg/kg) in anesthetized male lambs pretreated with atorvastatin (10 mg/kg/day, subcutaneously; 1 week) or vehicle (dimethyl sulfoxide 10% subcutaneously). Sildenafil (0.7 mg/kg intravenously) or saline infusions were performed 60 min after APT induction. Non-embolized control animals received saline. APT significantly increased pulmonary vascular resistance index (PVRI) and mean pulmonary artery pressure (MPAP) by approximately 310% and 258% respectively. While atorvastatin pretreatment attenuated these increases (~150% and 153%, respectively; P < 0.05), its combination with sildenafil was associated with lower increases in PVRI and MPAP (~32% and 36%, respectively). Gelatin zymography showed increased MMP-9 and MMP-2 levels in the bronchoalveolar lavage, and increased MMP-9 levels in plasma from embolized animals. Atorvastatin pretreatment attenuated bronchoalveolar lavage MMP-2 increases. The combination of drugs blunted the MMPs increases in bronchoalveolar lavage and plasma (P < 0.05). Neutrophils accumulated in bronchoalveolar lavage after APT, and atorvastatin pretreatment combined with sildenafil (but not atorvastatin alone) attenuated this effect (P < 0.05). APT increased lung lipid peroxidation and total protein concentrations in bronchoalveolar lavage, thus indicating oxidative stress and alveolar-capillary barrier damage, respectively. Both increases were attenuated by atorvastatin pretreatment alone or combined with sildenafil (P < 0.05). We conclude that pretreatment with atorvastatin protects against the pulmonary hypertension associated with APT and that sildenafil improves this response. These findings may reflect antioxidant effects and inhibited neutrophils/MMPs activation.

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    ABSTRACT: Activated matrix metalloproteinases (MMPs) cause cardiomyocyte injury during acute pulmonary thromboembolism (APT). However, the functional consequences of this alteration are not known. We examined whether doxycycline (a MMP inhibitor) improves right ventricle function and the cardiac responses to dobutamine during APT. APT was induced with autologous blood clots (350 mg/kg) in anaesthetized male lambs pre-treated with doxycycline (Doxy, 10 mg/kg/day, intravenously) or saline. Non-embolized control lambs received doxycycline pre-treatment or saline. The responses to intravenous dobutamine (Dob, 1, 5, 10 μg/kg/min.) or saline infusions at 30 and 120 min. after APT induction were evaluated by echocardiography. APT increased mean pulmonary artery pressure and pulmonary vascular resistance index by ~185%. Doxycycline partially prevented APT-induced pulmonary hypertension (P < 0.05). RV diameter increased in the APT group (from 10.7 ± 0.8 to 18.3 ± 1.6 mm, P < 0.05), but not in the Doxy+APT group (from 13.3 ± 0.9 to 14.4 ± 1.0 mm, P > 0.05). RV dysfunction on stress echocardiography was observed in embolized lambs (APT+Dob group) but not in embolized animals pre-treated with doxycycline (Doxy+APT+Dob). APT increased MMP-9 activity, oxidative stress and gelatinolytic activity in the RV. Although doxycycline had no effects on RV MMP-9 activity, it prevented the increases in RV oxidative stress and gelatinolytic activity (P < 0.05). APT increased serum cardiac troponin I concentrations (P < 0.05), doxycycline partially prevented this alteration (P < 0.05). We found evidence to support that doxycycline prevents RV dysfunction and improves the cardiac responses to dobutamine during APT.
    Journal of Cellular and Molecular Medicine 11/2013; · 4.75 Impact Factor
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