Inward remodeling follows chronic vasoconstriction in isolated resistance arteries.
The hypothesis was tested that chronic vasoconstriction is followed by a structural reduction in lumen diameter, measured at full dilation. An in vitro model of pressurized rat skeletal muscle arterioles was used. During a 3-day experimental period, constriction of active vessels was achieved with fetal calf serum or endothelin-1 (ET-1). Maximal dilation revealed inward remodeling from 179 +/- 6.5 microm lumen diameter on day 0 to 151 +/- 6.3 microm on day 3 at 75 mm Hg in vessels incubated with serum (n = 8). Similarly, ET-1 induced inward remodeling from 182 +/- 5.2 to 164 +/- 3.7 microm (n = 6). When constriction during organoid culture was inhibited with papaverin or verapamil, inward remodeling was fully prevented: 184 +/- 6.3 to 184 +/- 5.8 microm for papaverin (n = 6) and 174 +/- 5.5 to 177 +/- 7.4 microm for verapamil (n = 6). A chronic reduction in diameter without tone was achieved in vessels that were kept at a low pressure (2-5 mm Hg; n = 6). Here, no remodeling was found, thereby ruling out that a chronic reduction in diameter alone is sufficient for inward remodeling. These data show that a persistent active reduction in lumen diameter is followed by inward remodeling of arterioles.
Bakker
Erik N T P
EN
Academic Medical Center, University of Amsterdam, Department of Medical Physics and Cardiovascular Research, Institute Amsterdam (CRIA), The Netherlands.
van der Meulen
Esther T
ET
van den Berg
Bernard M
BM
Everts
Vincent
V
Spaan
Jos A E
JA
VanBavel
Ed
E
D000818:Animals; D001160:Arterioles / Q000502:physiology*; D002417:Cattle; D019332:Endothelin-1 / Q000494:pharmacology; D005312:Fetal Blood; D007700:Kinetics; D008297:Male; D008854:Microscopy, Electron; D018482:Muscle, Skeletal / Q000098:blood supply*; D009924:Organ Culture Techniques; D010208:Papaverine / Q000494:pharmacology; D011312:Pressure; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000494:pharmacology; D013373:Substance P / Q000494:pharmacology; D014661:Vasoconstriction; D014664:Vasodilation; D014700:Verapamil / Q000494:pharmacology
D019332:Endothelin-1; D012701:Serotonin; D013373:Substance P; D014700:Verapamil; D010208:Papaverine