Vasa Vasorum of Veins in Dog and Man

Abstract

In 1875, K8ster remarked that &dquo;the vasa nutritia (of veins) are extraordinarily more numerous than is ordinarily represented, and supply quite small veins, whose wall one thinks would surely be without vessels.&dquo;' Following these observations, the blood supply of the vein wall received little attention, although references to the vasa vasorum of veins can be found in the earlier literature.'-' On the other hand, the vasa vasorum of arteries have received considerable attention, and there have been numerous attempts to correlate disorders of the vasa vasorum with arterial pathology. More recently there has been a resurgence of interest in vasa vasorum of veins because of the increasing use of vein grafts to by-pass arterial blocks.Lepehne,l in 1919, first employed the benzidine reaction of hemoglobin for the purpose of staining hemoglobin specifically in tissue sections, and he noted that the resultant picture may resemble that obtained by injection of the vessels. O'Neill,' in 1947, first used the method to study vasa vasorum of veins, and he found there was a rich network in the adventitia, but he could not demonstrate them in the media and intima.During an investigation into the histology of canine autogenous vein grafts, it was found that ingrowth of vasa vasorum into the graft wall occurred despite attempts to exclude them.' These studies led to the present attempt to define vasa vasorum of veins more precisely. METHODThe benzidine and orthotolidine staining techniques were used to demonstrate the vasa vasorum. The method used was essentially that employed by 0'Neill;6 however, for the thicker-walled human long saphenous vein, orthotolidine was substituted for benzidine. Benzidine reacts with hydrogen peroxide, the reaction being catalyzed by hemoglobin, and red blood cells are stained brown. Thus only those vessels containing red blood cells are outlined.The veins examined included femoral and jugular veins and the inferior vena cava removed from dogs under general anesthesia; the long saphenous vein removed from human patients under local anesthesia during operations for varicose veins; human femoral veins obtained at postmortem ; and femoral and long saphenous veins taken from dissecting room cadavers and thus preserved in fixative. The diameters of vasa vasorum were measured with a traveling wire eyepiece micrometer (Zeiss)

Architectonic Arrangement of the Vasa Vasorum of the Human Great Saphenous Vein

“…We used dissections, India ink injections and routine histology of semithin tissue sections [18] and found that feeding vessels entered the venous wall at intervals of about 15 mm and that venae vasorum drained either into veins running in parallel to the incoming arterial feeders or into the terminal segments of the largest tributaries of the HGSV. Moreover, and in accordance with previous findings of Brook [4], neither by microdissections nor by injections of India ink or Mercox resin draining were venae vasorum found opening directly into the lumen of the HGSV stem. In a recent paper [19], we cast (replicated) the entire network of VV in selected segments of the HGSV by injection of a polymerizing resin (Mercox-Cl-2B) into the feeding arteries and documented the spatial arrangement of the VV by scanning electron microscopy (SEM) and measured VV diameters, intervascular and interbranching distances, as well as branching angles of selected VV using 3D morphometry [20].…”

“…While some authors report such a termination [33, 34] others deny it [4] or report that VV terminate in main tributaries [15]. We could not find a direct opening of venae vasorum into the lumen of HGSV as in all our specimens injected via the external iliac artery (India ink injections) or via the VV arterial feeders (Mercox resin injection) no injection material was found in the HGSV lumen.…”

“…The detailed arrangement of the VV of subcutaneous veins of humans was described, however, only during the last decades of the 20th century [2,3,4,5]. At the same time, progress in experimental and clinical vascular surgery led to a high concern about the VV of coronary arteries [6,7,8] and during systemic arteriosclerosis and hypertension [9, 10].…”

Role of Vasa Vasorum in Nourishment of the Aorta

“…Recent observa tions support this concept. The blood supply to veins is extensive, as vessels penetrate from the adventitia almost to the intima (11). In lym phatics, vessels penetrate deep into the smooth muscle (12).…”

Testicular microvascularization in the common tree shrew (Tupaia glis) as revealed by vascular corrosion cast/SEM and by TEM

“…It should be emphasized that this study is the first to elucidate that the coiling part of the testicular artery gives off small branches that divide into vasa vasorum supplying the wall of the pampiniform plexus. This finding is of interest because the vasa vasorum are usually found to supply the thick wall of the large vessels (Brook, 1977) whereas the wall of the pampiniform plexus in this species is somewhat thin. It is possible that these vasa vasorum play a role in controlling the blood flow rate and consequently the blood volume to the testis.…”