Venous myogenic tone: studies in human and canine vessels. Am J Physiol 1992 Aug;263(2 Pt 2):H315-20
Date
08/01/1992Pubmed ID
1510127DOI
10.1152/ajpheart.1992.263.2.H315Scopus ID
2-s2.0-0026665142 (requires institutional sign-in at Scopus site) 41 CitationsAbstract
Active and passive mechanical properties of human saphenous and canine femoral and saphenous vein segments were measured in vitro to assess the degree of pressure-dependent venous myogenic tone (% change in diameter, physiological saline solution vs. Ca(2+)-free solution) in these vessels. Stepwise elevation of intraluminal pressure from 2 to 20 mmHg caused an active myogenic response, which was calcium dependent. Side branches of human saphenous veins (OD at 20 mmHg: 1.92 +/- 0.15 mm control; 2.41 +/- 0.18 mm relaxed) displayed a larger degree of myogenic tone (approximately 25%) compared with dog saphenous (OD: 2.84 +/- 0.16 mm control; 2.89 +/- 0.16 mm relaxed) and femoral (OD: 3.56 +/- 0.32 control; 3.66 +/- 0.31 mm relaxed) veins (2-3%). This alteration in myogenic tone results in over 120% change in lumen capacity for the human saphenous vein, whereas for the dog saphenous and femoral veins, the change in lumen capacity is less than 10%. The vessels showed a constriction to norepinephrine as well as a reversible dilation to Ca(2+)-free perfusion. These results support the hypothesis that an active myogenic response may play an important role in the regulation of vascular capacity in the human saphenous vein, which is subject to substantial pressure variations due to changing orthostatic loads.
Author List
Bérczi V, Greene AS, Dörnyei G, Csengödy J, Hódi G, Kádár A, Monos EMESH terms used to index this publication - Major topics in bold
AnimalsDogs
Endothelium, Vascular
Femoral Vein
Humans
Microscopy, Electron, Scanning
Models, Cardiovascular
Muscle Tonus
Muscle, Smooth, Vascular
Pressure
Saphenous Vein
Veins
