VASCULAR ANATOMY OF THE RABBIT URETER

Background: The success of kidney transplant surgery and ureteral reco nstruction requires the preservation of the ureteral blood supply, Bec ause of its potential vulnerability to surgical trauma during transpla nt and reconstructive surgery, the ureteral vasculature merits a full anatomical description. Methods: The microvascular anatomy of the uret er was studied in male New Zealand white rabbits by light microscopy a nd transmission electron microscopy and scanning electron microscopy o f vascular corrosion casts and alkali digested tissue. Results: The ra bbit ureter is supplied predominantly by a branch of the renal artery proximally (cranial ureteral artery) and by a branch of the vesicular artery distally (caudal ureteral artery). Minor vascular continuities are also present between the capillary beds of the ureter and those of the renal pelvis cranially and the bladder wall caudally, There are n o external vascular connections to the middle ureter with the exceptio n of a single, small. vein which drains into the inferior vena cava. A single group of longitudinal arteries and veins runs the full length of the ureter within the adventitia, Branches of these longitudinal ve ssels pass tangentially through the muscularis to supply a vascular co mplex within the lamina propria. This complex in turn supports a rich, mucosal capillary plexus located at the junction between the transiti onal epithelium and the lamina propria, In the fixed ureter the capill ary plexus lies in grooves formed by displacement of the basal layers of the overlying transitional epithelium, The capillaries are continuo us or fenestrated, are often invested with pericytes, and are distribu ted uniformly around the entire circumference of the ureter. Conclusio ns: The ureteral vasculature exhibits several unique features related to its function in urine conduction and its ability to accommodate exp ansion and contraction. The combination of techniques used provides a clear three-dimensional view of this vasculature, Our findings also co nfirm that, because of its limited blood supply, the meter may be very susceptible to injury during renal transplantation or other abdominal surgery. (C) 1995 Wiley-Liss, Inc.