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Effect of Urinary Diversion on Calcium Metabolism and Growth: An Experimental Study with Rats
Accepted 421 ENHANCED INTRAVENOUS UROGRAPHY WITH LOW uOSE DOPAMINE: AN EXPERIMENTAL STUDY IN RATS WITH UNILATERAL TRAUMA OR OBSTRUCTION. *Prashant Mehta, *Yosh Taguchi and Irwin Kuzmarov, Montreal Que. Canada (Presentation to be made by Dr. Mehta) The intravenous pyelogram (IVP) is the standard first line investigation in the face of suspected renal injury. Occasionally, there may be nonvisualization or poor visualization on the side of injury raising concerns about a pedicle avulsion or tear. In a number of instances, the clinical assessment may suggest a much milder injury and the patient may be managed conservatively. If the pyelogram is repeated a day or so later, there may be prompt symmetrical excretion suggesting that the initial radiographic finding was the result of spasm rather than a pedicle avulsion or tear. The assumption of "mild" injury is dangerous and can lead to loss of renal units when it could have been salvaged. An animal model was created to simulate this clinical observation by crossclamping the renal pedicle of a rat with an unprotected artery forceps for a IO-minute period. An intravenous pyelogram done 1, 12 and 24 hours later revealed nonvisualization or poor visualization of the affected side. When the traumatized rats were treated with low dose Dopamine prior to the injection of contrast, there was marked improvement in the dye excretion of the damaged side. We then explored the "Dopamine" effect on rats with obstructed kidneys (ligated ureter) again showing better quality pyelogram, on a cross-over saline versus Dopamine study.
422 URODYNAMICS OF THE UPPER URINARY TRACT - PERCUTANEOUS PYELOMETROGRAPHY (PPMG). *Klaus P. Juenemann and *Patrick De Geeter, Kassel, FRG (Presentation to be made by Dr. Juenemann) For differential diagnosis of obstructive upper urinary tract dysfunction (UPJ-obstruction), PPMG is performed since 1984 in the Department of Urology, Kassel. After ultrasound controlled percutaneous nephrostomy, the intrarenal baseline pressure is measured for 10 minutes ("basic pressure") and the renal pelvis is filled with contrast medium to allow x-ray studies of the kidney. Subsequently, 20 mg Furosemid are injected intravenously to stimulate renal diuresis while the intrarenal pressure change is recorded ( "hydration pressure"); the wash-out effect of the contrast medium is observed by x-ray. 14 patients underwent PPMG evaluation for upper urinary tract obstruction; the results were compared with other non-invasive methods (radioisotopic renography, isotope wash-out test, hydration-IVP). In 9/14 cases, we found a correlation between obstructive PPMG (Ap >10-15 mbar) and the non-invasive tests. 3/7 patients demonstrated a nonobstructive upper urinary tract in PPMG (Ap <10 mbar), hydration-IVP and isotope studies; however, 2 other cases showed false positive (obstruction) results in the isotope renography and 2 demonstrated false negative (non-obstruction) results in comparison to PPMG. We conclude that PPMG is an excellent diagnostic method for functional evaluation of the upper urinary tract.
423
424
EFFECT OF URINARY DIVERSION ON CALCIUM METABOLISM AND GROWTH: AN EXPERIMENTAL STUDY WITH RATS. *Michael O. Koch and W. Scott McDougal, Nashville, TN (Presentation to be made by Dr. Koch)
EFFECTS OF CONVERTING ENZYME INHIBITION ON RENAL FUNCTION IN CHRONIC 2-KIDNEY, 1-CLIP HYPERTENSIVE DOGS. ''R. Ernest
Previous studies have demonstrated an adverse effect on calcium metabolism following chronic urinary diversion and in the absence of systemic acidosis. A group of female Wistar rats underwent unilateral ureterosigmoidostomy and were compared to a control group with respect to electrolyte abnormalities, body weight, bone growth and compensatory renal changes to urinary diversion after a 10 week period. No significant differences were found in serum electrolytes including serum bicarbonate, chloride, total calcium, phosphorus and ammonium. Serum ionized calcium
Sosa, New York, N.Y. (Presentation to be made by Dr. Sosa).
Converting enzyme inhibitors (CEI) produce reversible renal insufficiency when used to treat bilateral renovascu-
lar hypertension (RVH).
To study i:he effects of CEI on re-
nal function in unilateral RVH, chronic 2-kidney, 1-clip
(2K,1C) hypertensive dogs were established by snaring the renal artery to the left kidney (LK). Four weeks later, hypertensive dogs (n = 4) were instrumented under general anesthesia to measure mean arterial pressure (MAP), aortic
(A) plasma renin activity (PRA) and differential renal vein renins (RV) (ng/ml/h), glomerular filtration rate (GFR), renal blood flow (RBF). MK422 was administered as a bolus
was depressed in the ureterosigmoidostomy group (2.60 ± 1.11 vs. 3.67 ± .87, p <.05), however. Ureterosigmoidostomy
(5mg iv) and all parameters were remeasured every 30 mins for 2 hours (E), Measurements were repeated after a 60 min
rats also demonstrated impaired growth in body weight rela-
recovery (R). GFR remained unchanged in the contralateral ri.ght kidney (RK) but decreased in LK during E by> 50%. '' <*=p ~ 0. 05),
tive to controls at the end of 10 weeks (264 ± 10 g vs. 286 ± 16 g, p <. 01). Femoral wet bone weights were lower in the ureterosigrnoidostorny group (0.97 ± 0.06 g vs. 1.05 ± 0.08 g, p < .05) although this difference is lost when referenced to body weight. Renal clearance experiments were conducted on the contralateral undiverted renal units to demonstrate the renal adaptations that occur. Rats with ureterosigmoidostomies exhibit higher fractional calcium
excretions at all levels of sodium excretion (FE Ca= .925 FE Na+ .365, r = .926, p < .001 for controls; FE Ca= 1.259 FE Na+ 1.967, r = .628, p < .05 for ureterosigmoidostomy group). This experimental study demonstrates an adverse effect on growth and calcium homeostasis in animals that have undergone unilateral urinary diversion in the absence of systemic electrolyte alterations. This adverse effect may be secondary to an increased renal wastage of calcium. These findings have obvious clinical implications to patients with urinary diversions.
MAP
C (LK) (RK) E (LK) (RK) R (LK) (RK)
80 140 + 12 214 49 120 + 11'' 220 65 139 + 14 200
RBF
+ + + +
+ +
14 31 17'' 34 18 24
GFR 10 + 3 35 4 5 2* 36 5 6 + 2 35 6
+ + + +
PRA 16 + 4 99
±
27*
47 + 25
RV-A 41 + 10 0 226 + 45''
0
18 + 9
0
These data show that the CEI HK422 successfully lowers MAP in chronic 2K,IC hypertension, but produces a significant drop in GFR in the ischemic LK, strongly suggesting that CEis are not optimal alternatives for the treatment of RVH.
209A
422 URODYNAMICS OF THE UPPER URINARY TRACT - PERCUTANEOUS PYELOMETROGRAPHY (PPMG). *Klaus P. Juenemann and *Patrick De Geeter, Kassel, FRG (Presentation to be made by Dr. Juenemann) For differential diagnosis of obstructive upper urinary tract dysfunction (UPJ-obstruction), PPMG is performed since 1984 in the Department of Urology, Kassel. After ultrasound controlled percutaneous nephrostomy, the intrarenal baseline pressure is measured for 10 minutes ("basic pressure") and the renal pelvis is filled with contrast medium to allow x-ray studies of the kidney. Subsequently, 20 mg Furosemid are injected intravenously to stimulate renal diuresis while the intrarenal pressure change is recorded ( "hydration pressure"); the wash-out effect of the contrast medium is observed by x-ray. 14 patients underwent PPMG evaluation for upper urinary tract obstruction; the results were compared with other non-invasive methods (radioisotopic renography, isotope wash-out test, hydration-IVP). In 9/14 cases, we found a correlation between obstructive PPMG (Ap >10-15 mbar) and the non-invasive tests. 3/7 patients demonstrated a nonobstructive upper urinary tract in PPMG (Ap <10 mbar), hydration-IVP and isotope studies; however, 2 other cases showed false positive (obstruction) results in the isotope renography and 2 demonstrated false negative (non-obstruction) results in comparison to PPMG. We conclude that PPMG is an excellent diagnostic method for functional evaluation of the upper urinary tract.
423
424
EFFECT OF URINARY DIVERSION ON CALCIUM METABOLISM AND GROWTH: AN EXPERIMENTAL STUDY WITH RATS. *Michael O. Koch and W. Scott McDougal, Nashville, TN (Presentation to be made by Dr. Koch)
EFFECTS OF CONVERTING ENZYME INHIBITION ON RENAL FUNCTION IN CHRONIC 2-KIDNEY, 1-CLIP HYPERTENSIVE DOGS. ''R. Ernest
Previous studies have demonstrated an adverse effect on calcium metabolism following chronic urinary diversion and in the absence of systemic acidosis. A group of female Wistar rats underwent unilateral ureterosigmoidostomy and were compared to a control group with respect to electrolyte abnormalities, body weight, bone growth and compensatory renal changes to urinary diversion after a 10 week period. No significant differences were found in serum electrolytes including serum bicarbonate, chloride, total calcium, phosphorus and ammonium. Serum ionized calcium
Sosa, New York, N.Y. (Presentation to be made by Dr. Sosa).
Converting enzyme inhibitors (CEI) produce reversible renal insufficiency when used to treat bilateral renovascu-
lar hypertension (RVH).
To study i:he effects of CEI on re-
nal function in unilateral RVH, chronic 2-kidney, 1-clip
(2K,1C) hypertensive dogs were established by snaring the renal artery to the left kidney (LK). Four weeks later, hypertensive dogs (n = 4) were instrumented under general anesthesia to measure mean arterial pressure (MAP), aortic
(A) plasma renin activity (PRA) and differential renal vein renins (RV) (ng/ml/h), glomerular filtration rate (GFR), renal blood flow (RBF). MK422 was administered as a bolus
was depressed in the ureterosigmoidostomy group (2.60 ± 1.11 vs. 3.67 ± .87, p <.05), however. Ureterosigmoidostomy
(5mg iv) and all parameters were remeasured every 30 mins for 2 hours (E), Measurements were repeated after a 60 min
rats also demonstrated impaired growth in body weight rela-
recovery (R). GFR remained unchanged in the contralateral ri.ght kidney (RK) but decreased in LK during E by> 50%. '' <*=p ~ 0. 05),
tive to controls at the end of 10 weeks (264 ± 10 g vs. 286 ± 16 g, p <. 01). Femoral wet bone weights were lower in the ureterosigrnoidostorny group (0.97 ± 0.06 g vs. 1.05 ± 0.08 g, p < .05) although this difference is lost when referenced to body weight. Renal clearance experiments were conducted on the contralateral undiverted renal units to demonstrate the renal adaptations that occur. Rats with ureterosigmoidostomies exhibit higher fractional calcium
excretions at all levels of sodium excretion (FE Ca= .925 FE Na+ .365, r = .926, p < .001 for controls; FE Ca= 1.259 FE Na+ 1.967, r = .628, p < .05 for ureterosigmoidostomy group). This experimental study demonstrates an adverse effect on growth and calcium homeostasis in animals that have undergone unilateral urinary diversion in the absence of systemic electrolyte alterations. This adverse effect may be secondary to an increased renal wastage of calcium. These findings have obvious clinical implications to patients with urinary diversions.
MAP
C (LK) (RK) E (LK) (RK) R (LK) (RK)
80 140 + 12 214 49 120 + 11'' 220 65 139 + 14 200
RBF
+ + + +
+ +
14 31 17'' 34 18 24
GFR 10 + 3 35 4 5 2* 36 5 6 + 2 35 6
+ + + +
PRA 16 + 4 99
±
27*
47 + 25
RV-A 41 + 10 0 226 + 45''
0
18 + 9
0
These data show that the CEI HK422 successfully lowers MAP in chronic 2K,IC hypertension, but produces a significant drop in GFR in the ischemic LK, strongly suggesting that CEis are not optimal alternatives for the treatment of RVH.
209A