| Abstract: | ![]()
Intracellular sodium concentration in CCD fragments micro-dissected from the kidneys of 10-day and adult rats using fluorescent dye Na+ Green, was studied. The steady state level of intracellular sodium was lower in fragments from amiloride kidney (24.50 +/- 1.3 and 35.3 +/- 4.9 mM, n = 8, respectively). Amiloride reduced this parameter but, in the epithelia cells from immature kidney, the effect of imaloride was less pronounced. Fast nongenomic action of aldosterone on intracellular sodium concentration was found in both groups. Aldosterone significantly raised the steady state sodium level in epithelial cells in conditions of low sodium concentration (14 mM) in outer medium in both type of CCD fragments: from 10-day pups and adult animals (4.0 +/- 1, 5.5 +/- 0.5 and 5.1 +/- 0.2, 7.9 +/- 0.2 mM, n = 8). We suggest that, along with the well-known mineral-corticoid effect, aldosterone takes part in regulation of cell volume in CCD rat kidney from the earliest stages of postnatal ontogenesis. |
