Please use this identifier to cite or link to this item:
http://hdl.handle.net/1942/3807
Title: | Characteristics of the luminal proton pump in malpighian tubules of the ant | Authors: | DIJKSTRA, S LOHRMANN, E VAN KERKHOVE, Emmy GREGER, R |
Issue Date: | 1994 | Publisher: | KARGER | Source: | RENAL PHYSIOLOGY AND BIOCHEMISTRY, 17(1). p. 27-39 | Abstract: | The active pump mechanisms involved in K+ secretion of the malpighian tubules of the ant and present in the luminal membrane were investigated on isolated, luminally perfused tubules of Formica. The specific blocker for vacuolar type ATPases, bafilomycin A(1), was found to half-maximally inhibit secretion at a concentration of 10(-5) mol/l when added to the lumen. N-Ethylmaleimide reduced the calculated short circuit current (I-sc) to 78 and 21% of control value when added at 5.10(-4) mol/l, respectively, to the lumen and the bath. Reducing luminal pH inhibited I-sc with a half-maximal inhibition at a luminal pH of 4.5. Acidified omeprazole, Schering compound 28080 and vanadate (both 10(-3) and 10(-4) mol/l) inhibited I-sc only partially. The present data suggest that the luminal membrane of ant malpighian tubules contains a H+ pump. This pump is only poorly bafilomycin-sensitive. Furthermore, additional active transport systems responsible for secretion may be present. Part of these results have been published as abstracts. | Notes: | UNIV FREIBURG,INST PHYSIOL,W-7800 FREIBURG,GERMANY.DIJKSTRA, S, LIMBURGS UNIV CENTRUM,DEPT MBW,UNIV CAMPUS,GEBOUW D,B-3590 DIEPENBEEK,BELGIUM. | Keywords: | V-TYPE ATPASE; PROTON PUMP; LUMINAL PH; BAFILOMYCIN; MALPIGHIAN TUBULE; N-ETHYLMALEIMIDE; SCHERING COMPOUND; OMEPRAZOLE; VANADATE | Document URI: | http://hdl.handle.net/1942/3807 | ISI #: | A1994MM85700004 | Type: | Journal Contribution |
Appears in Collections: | Research publications |
Show full item record
WEB OF SCIENCETM
Citations
19
checked on Sep 28, 2024
Page view(s)
86
checked on Nov 7, 2023
Google ScholarTM
Check
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.