Collagenase degrades collagen in vivo in the ischemic heart.
Previously, we showed that ischemic rat heart contains an activated procollagenase capable of degrading collagen in vitro. We now demonstrate that the collagen resident in such hearts (in vivo) also becomes degraded, producing characteristic fragments implicating the action of an activated collagenase. The evidence is the appearance of amino-terminal dansyl-Ile (+dansyl-Leu) residues in pepsin digests of re-oxygenated rat hearts and immunoblots showing 3/4 length (alphaA) fragments from type I collagen. Also, in ischemic rat myocardium, alphaA(I) and alphaA(III) fragments were detected in pepsin digests. The time periods required for the cleavage and degradation of collagen suggest the participation of a procollagenase that becomes activated. Results demonstrate for the first time that an interstitial collagenase in such hearts initiates in vivo degradation of types I and III collagens.
Takahashi
S
S
Department of Medicine/Division of Cardiology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, USA.
Geenen
D
D
Nieves
E
E
Iwazumi
T
T
D000818:Animals; D003094:Collagen / Q000378:metabolism*; D017364:Collagenases / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D000860:Hypoxia / Q000378:metabolism; D015151:Immunoblotting; D008297:Male; D013058:Mass Spectrometry; D017202:Myocardial Ischemia / Q000378:metabolism*; D015425:Myocardial Reperfusion; D009206:Myocardium / Q000378:metabolism*; D010434:Pepsin A; D010446:Peptide Fragments / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar
D010446:Peptide Fragments; D003094:Collagen; D010434:Pepsin A; D017364:Collagenases