Effect of two week lymphatic occlusion on the mechanical properties of dog femoral arteries.
In order to study the long-term effect of impaired lymphatic drainage on the mechanical properties of the arterial wall, cylindrical femoral artery segments from 10 mongrel dogs after 2 weeks of hindlimb lymphatic occlusion were subjected to in vitro mechanical test and compared with the contralateral, sham-operated segments. Smooth muscle contraction was induced by norepinephrine (7.4 X 10(-6) M) and smooth muscle relaxation by papaverine (1.6 X 10(-4) M). As a result of 2 weeks of lymphatic occlusion, wall thickness increased from 243 +/- 18 to 343 +/- 35 microns (P less than 0.02), inner radius decreased from 1.69 +/- 0.11 to 1.42 +/- 0.12 mm (P less than 0.01) and elastic modulus decreased from 1.23 X 10(6) to 0.55 X 10(6) N/m2 (P less than 0.01), when determined at 100 mm Hg (13.3 kPa) intraluminal pressure and with relaxed smooth muscle. The contractile apparatus was able to produce active strain in the vessels with lymphostasis and at physiological pressures not significantly different from the controls (0.89 +/- 0.02 vs. 0.91 +/- 0.02), but at significantly lower levels of tangential stress. Active stress decreased significantly. This study shows that a reorganization of the vessel wall mechanical force-bearing elements occurs in lymphostasis, which, in some respects, resembles the mechanical alterations found in different forms of atherosclerosis.
Experimental Research Department, Semmelweis Medical University, Budapest, Hungary.
G L
GL
Nádasy
F
F
Solti
E
E
Monos
F
F
Schneider
V
V
Bérczi
A G
AG
Kovách
D000818:Animals; D001696:Biomechanical Phenomena; D004285:Dogs; D004548:Elasticity; D005263:Femoral Artery / Q000473:pathology / Q000502:physiology*; D008208:Lymphatic System / Q000502:physiology*; D008854:Microscopy, Electron; D013997:Time Factors; D014666:Vasomotor System / Q000502:physiology