Immunocytochemical Localization of Vitamin D-Dependent Calcium Binding Protein in Mammalian Nephron

Abstract

Immunoreactive calcium binding protein (iCaBP) has been localized in the rat nephron using the unlabeled antibody peroxidase-antiperoxidase immunocytochemical technique. Kidneys from normal young adult, vitamin D-deficient, and 12 day old rats were prepared by either freeze-substitution or 1% glutaraldehyde-Bouin's fixation. CaBP was localized with rabbit antiserum to chicken vitamin D-dependent intestinal CaBP. iCaBP was found specifically in the distal convoluted tubules (DCT); however, not all cells of the DCT were positive. In adult nephrons, a few scattered cells apparently belonging to the collecting tubules were positive. In the neonatal nephrons, there was also localization of iCaBP to the thick limb of Henle, suggesting a difference in the regulation of intracellular calcium during maturation. Proximal tubules, renal corpuscles, macula densa, and thin limbs of Henle gave no specific localization of iCaBP. These results present for the first time the localization of iCaBP in the mammalian nephron both in the neonate and in the young adult.

Immunohistochemical determination of calbindin-d28k in the kidney of postnatal rats

“…This localization of calbindin-D28k is similiar to results obtained in kidneys of several diverse species of vertebrates, mammalian (Rhoten and Christakos, 1981;Rhoten et al, 1985;Parmentier et al, 1987), and avian and reptilian (Rhoten et al, 1985;Parmentier et al, 1987).…”

“…These results represent a more extensive distribution of calbindin-D28k than tat found in the kidneys of any other animals investigated previously (Rhoten and Christakos, 1981;Taylor et al,1982;Schreiner et al, 1983;Rhoten et al, 1984) including the human (Roth et al, 1982). This statement is not strictly true as Rhoten et al (1982) reported immunoreactive calbindin-D28k in the medulla, including the ascending thick limb of the loop of Henle, as well as cortical labyrinth in neonatal rat kidney.…”

“…This group of proteins contain the common calcium ion binding motif known as EF-hand domain (Kretsinger et al, 1982). Calbindin-D28k has been reported in various species (Wasserman and Taylor, 1971;Fulmer and Wasserman, 1975;Rhoten et al, 1984Rhoten et al, , 1986 and in many tissues, including kidney (Hermsdorf and Bronner, 1975;Rhoten and Christakos, 1981;Rhoten et al, 1985), bone (Christakos and Norman, 1978), pancreas (Pochet et al, 1987), and the brain (Baimbridge et al, 1982;Feldman and Christakos, 1983).…”

Control of calbindin‐D28K expression in developing mouse kidney

“…The functional reasons for this difference remain obscure. Constitutive expression throughout the embryonic collecting duct tree is quite different from the cortically restricted, 1,25(0H),D3-dependent pattern reported in the adult (Taylor et al, 1982;Rhoten and Christakos, 1981;Roth et al, 1982). It is, however, analogous to the constitutive expression in the drainage channel of embryonic mesonephros, the Wolffian duct.…”

“…In the adult kidney, ~a 1 b i n d i n -D~~~ is found in the principal sites of calcium uptake-the distal convoluted and connecting tubules (Rhoten and Christakos, 1981;Roth et al, 1981Roth et al, , 1982Taylor et al, 1982;Rhoten et al, 1985). Present even before birth, its reported 0 1994 WILEY-LISS, INC. embryonic location foretells the adult expression pattern.…”