title: Chronic sildenafil treatment inhibits monocrotaline-induced pulmonary hypertension in rats.
abstract: Sildenafil, a phosphodiesterase 5 inhibitor, is currently under investigation for therapy of pulmonary hypertension. This study was designed to investigate chronic effects of sildenafil in monocrotaline (MCT)-induced pulmonary hypertension in rats. Four weeks after a single subcutaneous injection of MCT, the animals displayed nearly threefold elevated pulmonary artery pressure and vascular resistance values, with a concomitant decline in central venous oxygen saturation and arterial oxygenation. Marked right heart hypertrophy was evident, and massive thickening of the precapillary artery smooth muscle layer was histologically apparent. Further deterioration of pulmonary hypertension occurred 6 weeks after MCT injection, with some animals dying during this period because of right heart failure. When chronically administered from Days 14-28, sildenafil significantly increased plasma cyclic guanosine monophosphate and inhibited the development of pulmonary hypertension and right heart hypertrophy, with preservation of gas exchange and systemic arterial pressure. A corresponding efficacy profile was also noted for long-term feeding with sildenafil from Days 28-42. Moreover, the death rate significantly decreased in those animals treated with sildenafil. We conclude that sildenafil attenuates MCT-induced pulmonary hypertension and cor pulmonale in rats.
authors.affiliation: Department of Internal Medicine, Justus-Liebig-University Giessen, Giessen, Germany. ralph.schermuly@innere.med.uni-giessen.de
authors.forename: Ralph T
authors.initials: RT
authors.lastname: Schermuly
authors.forename: Klaus P
authors.initials: KP
authors.lastname: Kreisselmeier
authors.forename: Hossein A
authors.initials: HA
authors.lastname: Ghofrani
authors.forename: Hüseyin
authors.initials: H
authors.lastname: Yilmaz
authors.forename: Ghazwan
authors.initials: G
authors.lastname: Butrous
authors.forename: Leander
authors.initials: L
authors.lastname: Ermert
authors.forename: Monika
authors.initials: M
authors.lastname: Ermert
authors.forename: Norbert
authors.initials: N
authors.lastname: Weissmann
authors.forename: Frank
authors.initials: F
authors.lastname: Rose
authors.forename: Andreas
authors.initials: A
authors.lastname: Guenther
authors.forename: Dieter
authors.initials: D
authors.lastname: Walmrath
authors.forename: Werner
authors.initials: W
authors.lastname: Seeger
authors.forename: Friedrich
authors.initials: F
authors.lastname: Grimminger
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001707:Biopsy, Needle; D004195:Disease Models, Animal; D004334:Drug Administration Schedule; D004347:Drug Interactions; D006439:Hemodynamics / Q000187:drug effects; D006976:Hypertension, Pulmonary / Q000401:mortality / Q000473:pathology* / Q000517:prevention & control*; D007150:Immunohistochemistry; D008297:Male; D016686:Monocrotaline / Q000494:pharmacology; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D010879:Piperazines / Q000494:pharmacology*; D011336:Probability; D011660:Pulmonary Heart Disease / Q000473:pathology / Q000517:prevention & control*; D011687:Purines; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012680:Sensitivity and Specificity; D000068677:Sildenafil Citrate; D013450:Sulfones; D015996:Survival Rate; D013997:Time Factors
chemical_list: D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D013450:Sulfones; D016686:Monocrotaline; D000068677:Sildenafil Citrate