Abstract | BACKGROUND: METHODS: Adult Sprague-Dawley rats were housed in normoxia or hypoxia (FIO(2) = 10%) and administered vehicle or 100 mg/kg/day bosentan. After 3 weeks, echocardiographic and hemodynamic assessment was performed. PKC, procollagen-1 and collagen expression levels were assessed using immunoblot or colorimetric assay. RESULTS: RV systolic pressure (RVSP) and RVH were higher in hypoxic compared with normoxic animals (RVSP: 72 ± 4 vs 25 ± 2 mm Hg, p < 0.05; RVH: 1.2 ± 0.06 vs 0.5 ± 0.03 mg/g body weight, p < 0.05). Bosentan had no effect on RVSP or mass in normoxic animals, but did attenuate RVH in hypoxic animals (hypoxic/vehicle: 1.2 ± 0.06; hypoxic/ bosentan: 1.0 ± 0.05 mg/g body weight; p < 0.05). Hypoxia increased RV procollagen-1, and total collagen expression, effects that were attenuated by bosentan treatment. Hypoxia increased RV total and cytosolic PKC-δ protein expression, but had no effect on PKC-α or -ε isoforms. Administration with bosentan did not affect total PKC-δ protein expression. However, animals treated with bosentan had an increase in membranous PKC-δ when exposed to hypoxia. CONCLUSIONS:
Bosentan inhibits RVH and RV collagen expression in rats exposed to chronic hypoxia, possibly via alteration of PKC-δ activity.
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Authors | Gaurav Choudhary, Frederick Troncales, Douglas Martin, Elizabeth O Harrington, James R Klinger |
Journal | The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation
(J Heart Lung Transplant)
Vol. 30
Issue 7
Pg. 827-33
(Jul 2011)
ISSN: 1557-3117 [Electronic] United States |
PMID | 21550822
(Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, Non-P.H.S.)
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Copyright | Published by Elsevier Inc. |
Chemical References |
- Antihypertensive Agents
- Endothelin Receptor Antagonists
- Endothelin-1
- Protein Isoforms
- Sulfonamides
- Collagen
- Protein Kinase C
- Bosentan
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Topics |
- Animals
- Antihypertensive Agents
(pharmacology)
- Bosentan
- Collagen
(metabolism)
- Disease Models, Animal
- Endothelin Receptor Antagonists
- Endothelin-1
(metabolism)
- Fibrosis
- Hypertension, Pulmonary
(metabolism)
- Hypertrophy, Right Ventricular
(etiology, prevention & control)
- Hypoxia
(metabolism)
- Male
- Myocardium
(metabolism, pathology)
- Protein Isoforms
(metabolism)
- Protein Kinase C
(metabolism)
- Rats
- Rats, Sprague-Dawley
- Signal Transduction
- Sulfonamides
(pharmacology)
- Ventricular Dysfunction, Right
(complications)
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