抄録
It has been demonstrated that intercalated cells (ICs) change their cellular composition in acid stimuli in adult rabbits but not fully explained in developing rabbits. To clarify the mechanisms of adaptation in acid-base imbalance in collecting ducts in developing rabbit kidneys, we examined the cellular composition of cortical collecting ducts (CCDs) in 4-week-old rabbits. In the control group, the ratio of ICs to total CCD cells and that of peanut agglutinin (PNA) non-binding ICs to total ICs were 37.2±7.2% and 40.3±3.1%, respectively. By contrast, inconsistent with adult reports, in the acidotic group, these ratios were 38.4±5.1 % and 41.9±1.7%, respectively, similar to the control group. The urinary pH in the control group was 8.20±0.14, while that in acidemia was 4.98±0.33 (p<0.01). These data indicated that cellular remodeling of ICs in the acidotic state is less important for adaptation in the 4-week-old rabbit. Another mechanism, employing an acid-base related protein, might be playing an important role during development for acid base imbalance.
