Effects of maternal bilateral ureteral ligation on the development of the proximal tubule of the kidney in fetal rats: Morphometry and electron microscopic study

Abstract

Development of the proximal tubule in the fetal kidney was studied following ligation of both ureters of pregnant rats. The ligation was performed on days 15, 17, 19, and 21 of gestation and autopsy followed 24 hours after each operation. On fetal days 20 and 22, the proximal tubular length per unit volume (1 mm3) of whole kidney of the fetuses from the ligated mothers was significantly increased, while the ratio of total glomerular volume to total proximal tubular volume was remarkably decreased when compared to that of the fetuses from the non-ligated mothers. Apical vacuoles in proximal tubular cells were increased by the ligation on fetal days 20 and 22. These findings suggest that maternal bilateral ureteral ligation accelerates the growth and differentiation of the proximal tubule in fetal kidney, when the fetal kidney is functional in urine production.

Maternal renal insufficiency alters plasma composition and renal function in the fetal sheep

“…The differentiation of the glomerular membrane and maturation of the proximal tubule were accelerated by severe impairment of maternal renal function caused by bilateral ureteral ligation (18,19), and maternal unilateral nephrectomy increased the number and size of glomeruli in the offspring (20). We did not examine the fetal kidneys histologically, but even with our gross measures of renal weight and dimensions, we were able to demonstrate an abnormal growth pattern in the STNxF; i.e., their kidneys were wider than the kidneys of IntF so that their length-to-width ratio was reduced (Table 1).…”

Effects of Maternal Renal Dysfunction on Fetal Development

“…Fetal urine production is thereby stimulated by maternal ureteral ligation (Wells, 1946). We observed that in the kidney of fetuses of fetal days 20 and 22 from bilaterally ureter ligated mothers apical vacuoles in the proximal tubular cells are increased by the ligation (Okada & Morikawa, 1990). Furthermore, the surface area of the glomerular basement membrane and the length of the glomerular capillary per unit volume of glomerulus are increased (Okada & Morikawa, 1993) and shortening of the time for filtration of HRP through the glomerular basement membrane is observed in the fetuses from the ligated mothers (Okada et al, 1997).…”

Effects of maternal bilateral ureteral ligation on the differentiation of glomerular anionic sites in fetal rat kidney

“…x 26,500. , 1988) and the proximal tubules with relation to the glomerular functional development of kidney in fetal rats (Okada and Morikawa, 1990). Furthermore, the present results are supported by several lines of evidence concerning the onset of fetal kidney function in rats.…”