Collagen and Elastin Metabolism in Hypertensive Pulmonary Arteries of Rats

• Published in: Circulation research Vol. 66; no. 4; pp. 968 - 978
• Main Authors: Poiani, George J, Tozzi, Carol A, Yohn, Susan E, Pierce, Richard A, Belsky, Sandra A, Berg, Richard A, Yu, Shiu Y, Deak, Susan B, Riley, David J
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD American Heart Association, Inc 01.04.1990; Lippincott
• Subjects: Actins - genetics; Animals; Biological and medical sciences; Cardiology. Vascular system; Chronic cor pulmonale; Collagen - metabolism; Elastin - metabolism; Heart; Hypertension - metabolism; Hypertension - physiopathology; Medical sciences; Pneumology; Procollagen - genetics; Proteins - metabolism; Pulmonary Artery - metabolism; Pulmonary hypertension. Acute cor pulmonale. Pulmonary embolism. Pulmonary vascular diseases; Rats; Rats, Inbred Strains; RNA, Messenger - metabolism; Rat; Elastin; Rodentia; Cardiovascular disease; Glycoproteins; Metabolism; Pulmonary hypertension; Vertebrata; Experimental disease; Mammalia; Animal; Collagen; Pulmonary vascular disease
• ISSN: 0009-7330; 1524-4571
• DOI: 10.1161/01.RES.66.4.968

We evaluated the processes controlling the accumulation of collagen and elastin in main pulmonary arteries of rats during an episode of hypoxic pulmonary hypertension. Explant cultures of main pulmonary arteries were incubated with [H]proline to measure collagen and protein synthesis and percent collagen synthesis. Elastin synthesis was measured by [C] valine incorporation into insoluble elastin. Relative collagen synthesis increased twofold (from 1.1±0.2×10 to 2.0±1.0×10 disintegrations per minute [C]hydroxyproline/vessel/hr/mg protein), relative collagen synthesis doubled (from 2% to 4–5% of total protein synthesis), and elastin synthesis increased ninefold (from 0.4±0.2×10 to 3.6±0.6×10 dpm [C]valine/vessel/hr/mg protein) in early hypertension. The level of pro αl(I) collagen RNA paralleled the relative collagen synthetic rate during the study period. Within 7 days of recovery from hypoxia, collagen and elastin contents were normal. We conclude that collagen and elastin in main pulmonary arteries are synthesized rapidly during an episode of hypoxic pulmonary hypertension and that collagen and elastin are rapidly removed from the hypertensive vessel during normoxic recovery.