Reduction in Left Ventricular Messenger RNA for Transforming Growth Factor β 1 Attenuates Left Ventricular Fibrosis and Improves Survival Without Lowering Blood Pressure in the Hypertensive TGR(mRen2)27 Rat
| Autor: | Peter Kossmehl, Roland Lauster, Sara-Joan Pinto-Sietsma, Hans-Joachim Merker, Svenja Sethmann, Yigal M. Pinto, Sonja Engler, Martin Paul, Berthold Hocher, Tobias Philipp, Heike Marquardt |
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| Přispěvatelé: | Other departments, University of Groningen |
| Rok vydání: | 2000 |
| Předmět: |
Male
FIBROBLASTS medicine.medical_specialty Heart Diseases Heart Ventricles Tranilast Cardiomegaly Left ventricular hypertrophy AUTOCRINE PRODUCTION Losartan Rats Sprague-Dawley TRANILAST Fibrosis Internal medicine Renin–angiotensin system Internal Medicine medicine GROWTH-FACTOR-BETA-1 Animals Ventricular Function ortho-Aminobenzoates RNA Messenger CARDIAC-HYPERTROPHY GENE-EXPRESSION hypertension experimental FACTOR-BETA(1) EXPRESSION business.industry SMOOTH-MUSCLE CELLS Rats Inbred Strains medicine.disease Survival Analysis Angiotensin II Rats Disease Models Animal Endocrinology Blood pressure Transforming Growth Factors TRANSGENIC RATS Hypertension hypertrophy business Receptors Transforming Growth Factor beta RENIN-ANGIOTENSIN-SYSTEM medicine.drug Transforming growth factor |
| Zdroj: | Hypertension, 36(5), 747-754. Lippincott Williams and Wilkins Hypertension, 36(5), 747-754. LIPPINCOTT WILLIAMS & WILKINS |
| ISSN: | 1524-4563 0194-911X |
| DOI: | 10.1161/01.hyp.36.5.747 |
| Popis: | Abstract —Angiotensin II recruits transforming growth factor β 1 (TGFβ 1 ) and is related to left ventricular fibrosis. However, it is unclear whether chronic in vivo reduction in left ventricular TGFβ 1 expression blunts fibrosis and improves outcome in angiotensin II–dependent hypertension. Four-week-old male hypertensive TGR(mRen2)27 (Ren2) rats received either normal food, low-dose losartan (0.5 mg · kg −1 · d −1 ), or tranilast (a nonspecific TGFβ inhibitor; 400 mg · kg −1 · d −1 ) (n=10 for each group) for 12 weeks and were compared with Sprague-Dawley control rats. The effect of tranilast on survival was evaluated in 34 additional untreated homozygous Ren2 rats. Tranilast or low-dose losartan did not lower blood pressure. However, the increase in left ventricular weight (Ren2 versus SD 3.1±0.16 versus 2.1± 0.06 mg/g body wt; P P 1 mRNA and fibronectin mRNA and blunted the increase in hydroxyproline content and the increase in perivascular fibrosis. The perivascular fibrosis score correlated significantly with the level of expression of TGFβ 1 ( r =0.62; P =0.019). In situ hybridization demonstrated increases in TGFβ 1 mRNA, predominantly in perivascular and nonmyocyte areas. Both drugs did not prevent the decrease in systolic or diastolic dP/dt, but tranilast significantly improved the survival of untreated Ren2 rats ( P =0.029). In conclusion, TGFβ 1 mRNA expression is increased predominantly in nonmyocyte regions in the hypertrophied left ventricle in this angiotensin II–dependent model of hypertension. This increase is probably due to high angiotensin II levels rather than to hypertension. This is the first study to suggest that chronic inhibition of TGFβ 1 expression attenuates left ventricular hypertrophy and fibrosis, even without lowering blood pressure. |
| Databáze: | OpenAIRE |
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