ISSN:
1432-2013
Keywords:
Epithelial transport
;
Contraluminal cell membrane
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Abstract In order to study the specificity for the contraluminal sulfate transport system the inhibitory potency of sulfate esters and sulfonate compounds on the35SO 4 2− influx from the interstitium into cortical tubular cells in situ has been determined. The following was found: 1. From 10 sulfate monoesters tested 9 inhibited contraluminal sulfate influx with an app.K i between 0.6 and 6 mmol/l; the two sulfate diesters tested, however, did not. 2. Out of 8 aliphatic sulfonate compounds only three, having a NH- or OH-group in a suitable position, exerted a moderate inhibition (app.K i ca. 2–6 mmol/l). 3. Amongst 14 benzene sulfonates tested only 2 compounds (5-nitrobenzene-sulfonate and 2-hydroxy-5-nitrobenzenesulfonate) inhibited with aK i〈5 mmol/l. 4. Out of 10 naphthalene sulfonates tested 8 inhibited with aK i〈5; the highest inhibition was seen with the NH-containing 8-anilinonaphthalene-1-sulfonate (ANS), but no inhibition with 2 compounds containing an amino group. 5. From the polycyclic sulfonates pyrene-3-sulfonate and anthracene-1-sulfonate inhibited with aK i of approximately 2 mmol/l, while no inhibition was seen with anthracene-2-sulfonate. 6. Out of 4 amino-sulfonates tested benzene-1-amino-sulfonate and a similar benzyl-analog inhibited with aK i of 1 mmol/l and smaller; cyclohexyl-1-amino-sulfonate (cyclamate), however, inhibited only slightly (app.K i of 6 mmol/l). The data indicate that sulfate monoesters are well accepted by the contraluminal sulfate transport system. The affinity of sulfonate compounds to this system depends on neighbouring OH-groups −NH-groups, meta-positioned electronegative groups or a hydrophobic moiety in an appropriate position.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00585338
