STRUCTURAL-SPATIAL REMODELING OF VASCULAR BED OF HIND LIMBS IN RATS AT ACUTE ISCHEMIA

Abstract

The aim of the work. To establish the peculiarities of structural-spatial remodeling the arteries of the rat’s hind limbs by acute ischemia, caused by the application of an arterial tourniquet.

Materials and Methods. The X-ray angiography and morphometric study of the arterial vessels of the hind limbs of 30 rats under condition of experimental acute ischemia was performed. There were 6 intact animals in the control group. Acute ischemia was caused by application of SWAT rubber bands on the hind limbs of animals, 5–6 mm in width, at the inguinal fold level within 2 hours under thiopental  anesthesia. A reperfusion was modeled by removing the tourniquet.

The spatial organization of the arteries was studied in vascular branchings (tees): in the femoral area – at the place of the bifurcation of the muscular branch, in the popliteal area – at the site of bifurcation of the muscular cranial branch, and at the tibial area – at the site of the division of the popliteal artery on the cranial and caudal tibial arteries. In vascular tee the diameter of main trunk, the diameters of thicker and thinner arterial branch, the total angle of arterial branching and its components – the angle of deflection of thicker and thinner branch were measured.

Results and Discussion. Results of morphometric studies have established structural-spatial remodeling of the arterial bed of hind limbs of rats in the femoral, popliteal and tibial areas of the limb below the site of arterial tourniquet overlay. In the arterial tees of these areas of the limb an increase of average diameter of the main trunks of the arteries, which reached a maximum after 1 day of the experiment, was revealed. Thus, a maximum increase of diameter of the main trunk of the tee in the femoral area was 13.11 %, in the popliteal area – 13.95 %, and in the tibial – 14.99 % (for all groups p<0.05) in comparison with the control group. Herewith, the diameter of both thicker and (to a greater extent) thinner tee branch increased. Simultaneously an increase of the total branching angle of subsidiary branches in the femoral area by 9.02 %, in the popliteal area ­– by 8.89 %, and in the tibial area – by 6.36 % in comparison with the control group (for all p<0.05) was found, which was to a greater extent due to the increasing in the deviation of the thinner branch. After 14 days of reperfusion, the morphometric indices returned to the control group level.

Conclusions. The results of X-ray examination and morphometric study confirm the remodeling of the arteries  of the rats hind limbs as a result of the development of ischemia-reperfusion syndrome in experimental animals, which was manifested in increasing of the average dia­meter of the main trunks of the arteries of the vascular tees and in increasing of the branching angle of the both subsi­diary branches. Herewith, an increase of the diameters and deflection angles of both thicker and (to a greater extent) thinner tee branch was revealed.