LIGATION OF LEFT RENAL VEIN IN DOGS

Abstract

The renal vein is one of the most important veins in the body. Therefore, its obstruction causes various diseases, which may be fatal at times. On the other hand, it is said that the left kidney can retain its renal functions owing to its being rich in collateral circulation. However, no adequate studies have been carried out concerning this subject since a few number of investigations have been undertaken.
In this study in 31 mongrel dogs, the left renal veins of animals were ligated centrad to the confluence of the testicular vein in order to determine the course, global renal functions, fluctuations of the blood enzymes levels, renal histological changes, process of collateral vascularization and the left renal functions one to four weeks after the removal of the right (namely the opposite side) kidney.
1. Out of the 31 dogs with the left renal vein ligated, 28 dogs (93.5%) survived more than one to four weeks. This fact indicates that the ligature of the left renal vein of dogs is not always followed by fatal hemorrhage in the perirenal area or high mortality rate but can be tolerated adequately in general.
2. In 5 dogs in which determinations of the serum creatinine levels were carried out for 2 weeks after the ligature of the left renal vein, it was found that all the fluctuations remained within the normal limit.
3. The blood levels of GOT, GPT, alkaline phosphatase, LDH, and aldolase were determined in 5 dogs for 2 weeks after the ligature of the left renal vein. All the changes remained within normal limit in 3 dogs. However, in one of the remaining 2 dogs elevations of GOT, GPT, LDH and aldolase were seen and in the other those of GPT and alkaline phosphatase, although all of these changes were mild and transitory in nature. From these results it was considered that histological changes caused by the ligature of the left renal vein were mild.
4. Histological changes occurred under the ligature of the left renal vein included pronounced circulatory disturbances such as thickening of glomerular basal membrane, swelling of the proximal tubular epithelium, retention of albumin cast and dilatation of veins. Four weeks after the ligature, all of these lesions were decreased, and no organic changes were seen.
5. The main collateral vascularization under the ligature of the left renal vein consisted of testicular and ureteral veins, but renal capsular, adrenal and lumbar veins were also found to play roles in collateral circulation by forming netlike communication with testicular and ureteral veins.
6. In 12 dogs removed of the right kidney one to four weeks after the ligature of the left renal vein, the course after removal of the right kidney was observed. All of the dogs in which the right kidney was resected one to two weeks after the ligature died from renal insufficiency 5 to 6 days after the last operation. Out of the 4 dogs which were resected of the right kidney 3 weeks after the ligature, 2 dogs died from renal sufficiency 6 days after the operation, but the remaining 2 dogs survived. All of the 5 dogs which underwent resection of the right kidney 4 weeks after the operation survived with good renal function maintained. The measurements of serum creatinine and excretory urogram were normal.
From these results it was revealed that in dogs ligated of the left renal vein collateral circulation consisting chiefly of testicular and ureteral veins is established in 4 weeks after the operation with recovery of histological changes due to circulatory disturbances and that the left kidney can retain normal functions.