STUDIES OF THE HYDRODYNAMIC CHANGES IN THE URETER
MORPHOLOGICAL CHANGES OF THE RABBIT URETER FOLLOWING INTERNAL PRESSURE LOAD AND INFLUENCE OF AGING AND RESERPINE
1977 Volume 68 Issue 10 Pages 945-951
Details
1977 Volume 68 Issue 10 Pages 945-951
Changes of the rabbit ureter (central portion) following an intraluminal pressure load, especially the time course of changes during the period of hydroureter formation were studied with special reference to (1) effect of the administration of reserpine and (2) effect of aging or the difference between ureter of the newborn and that of the adult. The ureter of a rabbit after acute death was perfused with a modified tyrode solution (37±0.2°C, pH 7.2, saturated with 95% O2+5% CO2) in a muscle chamber. The distal end of the ureter was ligated and the proximal end was cannulated. Via this cannula, pressures of 10, 20 and 40 cm H2O were applied for at least 4 hours. The morphological changes of the ureter were photographically recorded in chronological sequence. In the photograph, the changes of the diameter of the ureter (measured as the maximum diameter) and the length (measured on the midline) were studied. The control and reserpinized groups were compared. In the reserpinized group, 2mg/kg of reserpine was intramuscularly injected 24 and 48 hours prior to the experiment. The diameter and the length were measured before loading and the ratio between these and the values after loading were calculated.
The following results were obtained.
(1) Reserpine augmented the increase in the diamter of the ureter of adult rabbit (dilatation) at low pressures of loading, 10 and 20cm H2O.
(2) The effect of reserpine was scarcely noted on an increase of length of the ureter of adult rabbit (tortuosity).
(3) Reserpine augmented the increase in the diameter of the ureter of neonatal rabbit (a) at earlier times and (b) at more multiple sites compared to the controls. Detailed morphological studies revealed corrugate formation in the reserpinized group compared to the balloon formation in the control group.
(4) The effect of reserpine was scarecely noted on an increase of the long diameter of the ureter of the newborn rabbit (tortuosity).
