Successive histochemical differentiation steps during postnatal development of the collecting duct in rabbit kidney

We recently isolated a cDNA encoding a Na+/Ca2+ exchanger from rabbit kidney that was highly similar to the canine cardiac sarcolemmal Na+/Ca2+ exchanger. In the present study, we used two different antibodies to the exchanger to identify the protein and establish its cellular and subcellular localization in the kidney. The first antibody was prepared against a fusion protein consisting of 190 amino acids of the large, presumably intracellular loop of the rabbit renal exchanger fused to the maltose-binding protein. The second was a monoclonal antibody generated against the isolated purified canine cardiac sarcolemmal exchanger. To identify the Na+/Ca2+ exchanger protein, we performed immunoblot analysis against a membrane vesicle preparation from rabbit kidney cortex. Both antibodies immunoblotted proteins of 120 and 70 kDa that are known to be associated with the exchanger. Indirect immunofluorescence revealed that both antisera labeled the basolateral surface of the majority of cells in the connecting tubule (CNT). Since the phase-dense (intercalated) cells in the CNT were not stained, this suggested that the labeled cells were CNT cells. No labeling was detected in other nephron segments with the exception of occasional faint staining of the majority cell population of the cortical collecting duct. The fact that we did not detect labeling in other nephron segments is consistent with either 1) the absence of expression of the Na+/Ca2+ exchanger in these segments, 2) the expression of the exchanger in levels below the threshold of detection of the two antibodies used in this study, or 3) the exchanger in these segments is represented by a different isoform.(ABSTRACT TRUNCATED AT 250 WORDS)

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Conductive properties of the rabbit outer medullary collecting duct: inner stripe

AJP Renal Physiology ◽

10.1152/ajprenal.1985.248.4.f500 ◽

1985 ◽

Vol 248 (4) ◽

pp. F500-F506 ◽

Cited By ~ 8

Author(s):

B. M. Koeppen

Keyword(s):

Cell Membrane ◽

Collecting Duct ◽

Basolateral Membrane ◽

Apical Cell ◽

Rabbit Kidney ◽

Apical Cell Membrane ◽

Basolateral Cell Membrane ◽

Medullary Collecting Duct ◽

Conductive Properties

Segments of outer medullary collecting duct were dissected from the inner stripe of the rabbit kidney (OMCDi) and perfused in vitro. The conductive properties of the tubule epithelium and individual cell membranes were determined by means of cable analysis and intracellular voltage-recording microelectrodes. In 35 tubules the transepithelial voltage (VT) and resistance (RT) averaged 17.2 +/- 1.4 mV, lumen positive, and 58.6 +/- 5.3 k omega X cm, respectively. The basolateral membrane voltage, (Vbl) was -29.2 +/- 2.1 mV (n = 23). The apical cell membrane did not contain appreciable ion conductances, as evidenced by the high values of apical cell membrane fractional resistance (fRa = Ra/Ra + Rb), which approached unity (0.99 +/- 0.01; n = 23). Moreover, addition of amiloride or BaCl2 to the tubule lumen was without effect on the electrical characteristics of the cell, as was a twofold reduction in luminal [Cl-]. The conductive properties of the basolateral cell membrane were assessed with bath ion substitutions. A twofold reduction in bath [Cl-] depolarized Vbl by 14.7 +/- 0.4 mV (theoretical, 17 mV), while a 10-fold increase in bath [K+] resulted in only a 0.9 +/- 0.4 mV depolarization (theoretical, 61 mV). Substituting bath Na+ with tetramethylammonium (from 150 to 75 mM) was without effect. Reducing bath [HCO-3] from 25 to 5 mM (constant PCO2) resulted in a steady-state depolarization of Vbl of 8.4 +/- 0.4 mV that could not be attributed to conductive HCO-3 movement. Thus, the basolateral cell membrane is predominantly Cl- selective.(ABSTRACT TRUNCATED AT 250 WORDS)

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Successive lectin-binding changes within the collecting duct during post-natal development of the rabbit kidney

Pediatric Nephrology ◽

10.1007/bf00869833 ◽

1990 ◽

Vol 4 (5) ◽

pp. 505-509 ◽

Cited By ~ 8

Author(s):

W. W. Minuth ◽

U. Rudolph

Keyword(s):

Collecting Duct ◽

Lectin Binding ◽

Rabbit Kidney

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Insulin-like growth factor I receptor gene expression during postnatal development of rabbit kidney

The Anatomical Record ◽

10.1002/(sici)1097-0185(199710)249:2<187::aid-ar5>3.0.co;2-v ◽

1997 ◽

Vol 249 (2) ◽

pp. 187-195 ◽

Cited By ~ 3

Author(s):

José L. Ojeda ◽

M. Teresa Berciano ◽

José I. Polanco ◽

Miguel Lafarga ◽

José C. Rodríguez-Rey

Keyword(s):

Gene Expression ◽

Growth Factor ◽

Postnatal Development ◽

Receptor Gene ◽

Rabbit Kidney ◽

Insulin Like Growth Factor ◽

Factor I ◽

Growth Factor I ◽

Receptor Gene Expression

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Carbonic anhydrase II mRNA is induced in rabbit kidney cortex during chronic metabolic acidosis

AJP Renal Physiology ◽

10.1152/ajprenal.1993.265.6.f764 ◽

1993 ◽

Vol 265 (6) ◽

pp. F764-F772 ◽

Cited By ~ 4

Author(s):

G. J. Schwartz ◽

C. A. Winkler ◽

B. J. Zavilowitz ◽

T. Bargiello

Keyword(s):

Metabolic Acidosis ◽

Carbonic Anhydrase ◽

Collecting Duct ◽

Carbonic Anhydrase Ii ◽

Northern Analysis ◽

Rabbit Kidney ◽

Kidney Cortex ◽

Rt Pcr ◽

Chronic Metabolic Acidosis ◽

Pcr Product

Carbonic anhydrase II (CA II), the predominant isoform of carbonic anhydrase in the kidney, is believed to be localized primarily in the cytoplasm of proximal tubule and collecting duct intercalated cells. Carbonic anhydrase facilitates H+ secretion by catalyzing the formation of HCO3- from OH- in the presence of CO2. We have shown that renal cortical CA II activity is stimulated during 4-6 days of chronic metabolic acidosis [L.P. Brion, B.J. Zavilowitz, O. Rosen, and G.J. Schwartz. Am. J. Physiol. 261 (Regulatory Integrative Comp. Physiol. 30): R1204-R1213, 1991]. The purpose of these studies was to examine under similar conditions the regulation of CA II mRNA. We obtained a major portion of the rabbit CA II cDNA by reverse transcription of total RNA from rabbit kidney followed by amplification using oligonucleotide primers prepared from conserved areas in the coding regions of human, mouse, and chick CA II cDNAs in a polymerase chain reaction (RT-PCR). The 696-bp RT-PCR product was sequenced and found to be 71-86% homologous to CA II cDNAs from the other three species. The deduced amino acid sequence agreed closely (> 97%) with a previous Edman analysis of rabbit erythrocyte CA II. Northern analysis showed expression of a approximately 1.4 kb RNA, with cortex > outer medulla > inner medulla. Steady-state mRNA expression from kidney cortex of acid-treated rabbits was about twice that from controls, when normalized to the expression of beta-actin or malate dehydrogenase. The stimulation of CA II mRNA was greater after 3 days than after 5-6 days of acid treatment. (ABSTRACT TRUNCATED AT 250 WORDS)

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Carbonic anhydrase II and IV mRNA in rabbit nephron segments: stimulation during metabolic acidosis

AJP Renal Physiology ◽

10.1152/ajprenal.1998.274.2.f259 ◽

1998 ◽

Vol 274 (2) ◽

pp. F259-F267 ◽

Cited By ~ 8

Author(s):

Shuichi Tsuruoka ◽

Ann M. Kittelberger ◽

George J. Schwartz

Keyword(s):

Metabolic Acidosis ◽

Carbonic Anhydrase ◽

Mrna Expression ◽

Collecting Duct ◽

Proximal Tubules ◽

Rabbit Kidney ◽

Rt Pcr ◽

Chronic Metabolic Acidosis ◽

Nephron Segments ◽

Medullary Collecting Duct

Carbonic anhydrase (CA) facilitates renal bicarbonate reabsorption and acid excretion. Cytosolic CA II catalyzes the buffering of intracellular hydroxyl ions by CO2, whereas membrane-bound CA IV catalyzes the dehydration of carbonic acid generated from the secretion of protons. Although CA II and IV are expressed in rabbit kidney, it is not entirely clear which segments express which isoforms. It was the purpose of this study to characterize the expression of CA II and CA IV mRNAs by specific segments of the nephron using semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) and to determine the effect of chronic metabolic acidosis on CA expression by those segments. Individual nephron segments (usually 1–2 mm) were isolated by microdissection and subjected to RT-PCR. Amplification was performed simultaneously for CA IV, CA II, and malate dehydrogenase (MDH), a housekeeping gene. The intensities of the PCR products were quantitated by densitometry. CA IV mRNA was expressed by S1 and S2 proximal tubules and by outer medullary collecting duct from inner stripe (OMCDi) and outer stripe and initial inner medullary collecting duct (IMCDi). CA II mRNA was expressed by S1, S2, and S3 proximal tubules, thin descending limb, connecting segment (CNT), and all collecting duct segments. Acid loading induced CA IV mRNA expression in S1 and S2 proximal tubules and in OMCDi and IMCDi. CA II mRNA was induced by acidosis in all three proximal segments and nearly all distal segments beginning with CNT. No upregulation of MDH mRNA expression occurred. These adaptive increases in CA II and IV mRNAs are potentially important in the kidney’s adaptation to chronic metabolic acidosis.

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Primary culture of collecting duct cell epithelium from neonate rabbit kidney in monolayer

Experimental Physiology ◽

10.1113/expphysiol.1992.sp003567 ◽

1992 ◽

Vol 77 (1) ◽

pp. 129-139 ◽

Cited By ~ 5

Author(s):

S White ◽

H Reeve

Keyword(s):

Primary Culture ◽

Collecting Duct ◽

Duct Cell ◽

Rabbit Kidney

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Fibroblasts of rabbit kidney in culture. II. Paracrine stimulation of papillary fibroblasts by PDGF

AJP Renal Physiology ◽

10.1152/ajprenal.1991.261.2.f292 ◽

1991 ◽

Vol 261 (2) ◽

pp. F292-F299 ◽

Cited By ~ 6

Author(s):

A. Knecht ◽

L. G. Fine ◽

K. S. Kleinman ◽

H. P. Rodemann ◽

G. A. Muller ◽

...

Keyword(s):

Growth Factor ◽

Epithelial Cells ◽

Conditioned Medium ◽

Transforming Growth Factor Beta ◽

Transforming Growth Factor ◽

Interstitial Fibrosis ◽

Collecting Duct ◽

Rabbit Kidney ◽

Fibroblast Growth ◽

Igf I

To examine the role of tubulointerstitial cell interaction in the regulation of fibroblast growth, fibroblasts from the rabbit renal cortex (CF) and papilla (PF) were cocultured with epithelial cells from the same tissue location. Inner medullary collecting duct epithelial cells (IMCDE) or IMCDE-conditioned medium stimulated DNA synthesis in PF, whereas proximal tubule epithelium (PTE) had no effect on the proliferation of CF. PF and CF showed a similar mitogenic response to exogenous epidermal growth factor and insulin-like growth factor 1 (IGF-I). Transforming growth factor-beta 1 inhibited growth of both cell types, and basic fibroblast growth factor (bFGF) had no effect on proliferation of either cell type. In contrast, platelet-derived growth factor (PDGF) was a potent mitogen for PF but was only weakly mitogenic for CF. Both CF and PF expressed a similar number of a single-affinity class of PDGF receptors (Kd, 2-4 x 10(-10) M). Assay for growth factor activity in conditioned medium from IMCDE and PTE showed that only IMCDE produced detectable PDGF. IMCDE-stimulated proliferation of PF was partially blocked by an antibody to PDGF, whereas antibodies to IGF-I had no neutralizing effect. The data suggest a role for PDGF in the regulation of interstitial fibroblast proliferation by IMCDE in the renal papilla. This paracrine system may be important in the pathogenesis of some forms of interstitial fibrosis of the kidney.

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