scholarly journals Proximal convoluted tubules of the rats kidney--a stereological analysis

2003 ◽  
Vol 3 (1) ◽  
pp. 36-39 ◽  
Author(s):  
Selma Aličelebić

Background and Purpose: The aim of this work was to order quantitative parameters of the proximal convoluted tubules (PCT) in the normal rat kidney cortex. Volume density (VV), both surface and specific surface density toward interstitium (SVi and SVi/VV) and toward lumen (SVl and SVl/VV) and thickness (T) of tubules epithelium have been stereologically ordered.Material and Methods: Stereologically were analysed 170 test fields by lattice L36 on the paraffin sections of the three adult male Wistar rats kidney dyeing by PAS-method.Results: The mean values of the variables analysed were Vv=76.4% ±0.012; Svi=0.056pm-1 ±0.004; Svl=0.028pm-1 ±0.003; Svi/Vv=0.073pm-1 ±0.003; Svl/Vv=0.037pm-1 ±0.005; T=18,26pm ±0.897.Conclusions: Stereological methods are making a very valuable contribution to science over recent years. We have used unbiased stereological counting methods to obtain objective quantitative parameters of the PCT epithelium in the normal rats’ kidney cortex.

1992 ◽  
Vol 282 (2) ◽  
pp. 369-375 ◽  
Author(s):  
S N Dhanakoti ◽  
M E Brosnan ◽  
G R Herzberg ◽  
J T Brosnan

Rat kidneys extract citrulline derived from the intestinal metabolism of glutamine and convert it stoichiometrically into arginine. This pathway constitutes the major endogenous source of arginine. We investigated the localization of enzymes of arginine synthesis, argininosuccinate synthase and lyase, and of breakdown, arginase and ornithine aminotransferase, in five regions of rat kidney, in cortical tubule fractions and in subcellular fractions of cortex. Argininosuccinate synthase and lyase were found almost exclusively in cortex. Arginase and ornithine aminotransferase were found in inner cortex and outer medulla. Since cortical tissue primarily consists of proximal convoluted and straight tubules, distal tubules and glomeruli, we prepared cortical tubule fragments by collagenase digestion of cortices and fractionated them on a Percoll gradient. Argininosuccinate synthase and lyase were found to be markedly enriched in proximal convoluted tubules, whereas less than 10% of arginase and ornithine aminotransferase, were recovered in this fraction. Arginine production from citrulline was also enriched in proximal convoluted tubules. Subcellular fractionation of kidney cortex revealed that argininosuccinate synthase and lyase are cytosolic. We therefore conclude that arginine synthesis occurs in the cytoplasm of the cells of the proximal convoluted tubule.


1994 ◽  
Vol 269 (9) ◽  
pp. 6637-6639
Author(s):  
A. Werner ◽  
S.A. Kempson ◽  
J. Biber ◽  
H. Murer

1973 ◽  
Vol 158 (2) ◽  
pp. 597-604 ◽  
Author(s):  
Åke Ellin ◽  
Sten Orrenius ◽  
Åke Pilotti ◽  
Carl-Gunnar Swahn

1978 ◽  
Vol 172 (1) ◽  
pp. 57-62 ◽  
Author(s):  
W Haase ◽  
A Schäfer ◽  
H Murer ◽  
R Kinne

Orientation of rat renal and intestinal brush-border membrane vesicles was studied with two independent methods: electron-microscopic freeze-fracture technique and immunological methods. With the freeze-fracture technique a distinct asymmetric distribution of particles on the two membrane fracture faces was demonstrated; this was used as a criterion for orientation of the isolated membrane vesicles. For the immunological approach the accessibility or inaccessibility of aminopeptidase M localized on the outer surface of the cell membrane to antibodies was used. With both methods we showed that the brush-border membrane vesicles isolated from rat kidney cortex and from rat small intestine for transport studies are predominantly orientated right-side out.


Author(s):  
Kodo Ito ◽  
Kenichi Yamada ◽  
Setsuko Yoshida ◽  
Keiji Hasunuma ◽  
Yasushi Tamura ◽  
...  

2003 ◽  
Vol 285 (3) ◽  
pp. C608-C617 ◽  
Author(s):  
Snezana Petrovic ◽  
Liyun Ma ◽  
Zhaohui Wang ◽  
Manoocher Soleimani

SLC26A6 (or putative anion transporter 1, PAT1) is located on the apical membrane of mouse kidney proximal tubule and mediates [Formula: see text] exchange in in vitro expression systems. We hypothesized that PAT1 along with a [Formula: see text] exchange is present in apical membranes of rat kidney proximal tubules. Northern hybridizations indicated the exclusive expression of SLC26A6 (PAT1 or CFEX) in rat kidney cortex, and immunocytochemical staining localized SLC26A6 on the apical membrane of proximal tubules, with complete prevention of the labeling with the preadsorbed serum. To examine the functional presence of apical [Formula: see text] exchanger, proximal tubules were isolated, microperfused, loaded with the pH-sensitive dye BCPCF-AM, and examined by digital ratiometric imaging. The pH of the perfusate and bath was kept at 7.4. Buffering capacity was measured, and transport rates were calculated as equivalent base flux. The results showed that in the presence of basolateral DIDS (to inhibit [Formula: see text] cotransporter 1) and apical EIPA (to inhibit Na+/H+ exchanger 3), the magnitude of cell acidification in response to addition of luminal Cl– was ∼5.0-fold higher in the presence than in the absence of [Formula: see text]. The Cl–-dependent base transport was inhibited by ∼61% in the presence of 0.5 mM luminal DIDS. The presence of physiological concentrations of oxalate in the lumen (200 μM) did not affect the [Formula: see text] exchange activity. These results are consistent with the presence of SLC26A6 (PAT1) and [Formula: see text] exchanger activity in the apical membrane of rat kidney proximal tubule. We propose that SLC26A6 is likely responsible for the apical [Formula: see text] (and Cl–/OH–) exchanger activities in kidney proximal tubule.


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