Remodeling
of the Rat Saphenous Vein Network in Response to Long-Term
Gravitational Load
M. LÓRÁNT, G. L. NÁDASY, G. RAFFAI, E. MONOS
Institute of Human Physiology and Clinical Experimental
Research, Semmelweis University, Budapest, Hungary
Received June 10, 2002
Accepted October 25, 2002
Summary
Our main objective was to test whether chronic orthostatic body
position induces network changes in the saphenous vein
superficial tributary system of the rat. Fourteen male Sprague-Dawley
rats were kept in tilted tube cages (45º head-up position) for
two weeks to induce chronic gravitational load to their leg
veins. Ten animals housed in normal cages and four animals kept
in horizontally positioned tube cages served as controls. The
whole superficial network of the left saphenous vein was
microprepared surgically under anesthesia, superfused with
saline and observed under a videomicroscope, while normal flow
and pressure were maintained in the lumen. Branching angles,
lengths of venous segments and their diameters were measured
offline from digitized images using special image-analyzing
software. Several branching angles at the popliteal confluence
were significantly reduced by 12.5-15.8 %. The in vivo diameter
of the main branch (936±34 vs. 805±44 µm) and of one of the
popliteal tributaries (776±38 vs. 635±36 µm) increased (p<0.05),
comparing vessels from tilted animals with those from normal
controls. Maintaining the animals in horizontal tube cages did
not induce the above alterations. The increased diameters and
reduced branching angles of the saphenous vein network observed
are adaptive responses of the venous network to a long-term
gravitational load.
Key words
Mapping • Microcirculation • Remodeling • Veins • Gravitational
load
Reprint requests
G.L. Nádasy MD PhD, Institute of Human Physiology and Clinical
Experimental Research, Semmelweis University, Üllői út 78/a,
H-1082 Budapest, Hungary, email:
nadasy@elet2.sote.hu
|