Advanced

Ornithine metabolism along the female mouse nephron: localization of ornithine decarboxylase and ornithine aminotransferase

Levillain, O; Diaz, J J; Reymond, I and Soulet, Denis LU (2000) In Pflügers Archiv 440(5). p.761-769
Abstract
The fate of ornithine in the nephron of the female OF-1 Swiss mouse remains unknown. The aim of the present study was to identify the nephron segments containing the key enzymes involved in ornithine metabolism: ornithine decarboxylase (ODC) and ornithine aminotransferase (OAT). Viable tubules isolated by microdissection were incubated with [1-14C]ornithine to study the oxidative pathway. Other tubules were permeabilized to measure the ODC activity. Ornithine was decarboxylated in all intact tubules. Gabaculine, a suicide inhibitor of OAT, and rotenone sharply decreased the production of 14CO2 from [1-14C]ornithine. No ODC activity was found in permeabilized tubules isolated from untreated mice. Testosterone increased ODC activity in the... (More)
The fate of ornithine in the nephron of the female OF-1 Swiss mouse remains unknown. The aim of the present study was to identify the nephron segments containing the key enzymes involved in ornithine metabolism: ornithine decarboxylase (ODC) and ornithine aminotransferase (OAT). Viable tubules isolated by microdissection were incubated with [1-14C]ornithine to study the oxidative pathway. Other tubules were permeabilized to measure the ODC activity. Ornithine was decarboxylated in all intact tubules. Gabaculine, a suicide inhibitor of OAT, and rotenone sharply decreased the production of 14CO2 from [1-14C]ornithine. No ODC activity was found in permeabilized tubules isolated from untreated mice. Testosterone increased ODC activity in the proximal tubule substantially and to a minor extent in other nephron segments. In situ hybridization showed ODC messenger ribonucleic acid (mRNA) to be absent in kidneys of untreated females but abundant in the cortex and the outer stripe of the outer medulla of testosterone-treated female mice. The whole proximal tubule contained a great density of silver grains corresponding to ODC mRNA. In conclusion, no basal ODC activity was found in the nephron of female mice. The testosterone-inducible ODC is localized mainly in the proximal tubule, but is also present in distal tubules and collecting ducts. OAT is distributed along the whole nephron, but its activity is higher in proximal tubules than in distal tubules. (Less)
Please use this url to cite or link to this publication:
author
publishing date
type
Contribution to journal
publication status
published
subject
in
Pflügers Archiv
volume
440
issue
5
pages
761 - 769
publisher
Springer
external identifiers
  • pmid:11007319
  • scopus:0033816320
ISSN
0031-6768
DOI
10.1007/s004240000340
language
English
LU publication?
no
id
3e967101-791c-4215-87b3-6c004fe65b0b (old id 1118255)
date added to LUP
2008-06-17 14:36:54
date last changed
2017-04-02 04:03:45
@article{3e967101-791c-4215-87b3-6c004fe65b0b,
  abstract     = {The fate of ornithine in the nephron of the female OF-1 Swiss mouse remains unknown. The aim of the present study was to identify the nephron segments containing the key enzymes involved in ornithine metabolism: ornithine decarboxylase (ODC) and ornithine aminotransferase (OAT). Viable tubules isolated by microdissection were incubated with [1-14C]ornithine to study the oxidative pathway. Other tubules were permeabilized to measure the ODC activity. Ornithine was decarboxylated in all intact tubules. Gabaculine, a suicide inhibitor of OAT, and rotenone sharply decreased the production of 14CO2 from [1-14C]ornithine. No ODC activity was found in permeabilized tubules isolated from untreated mice. Testosterone increased ODC activity in the proximal tubule substantially and to a minor extent in other nephron segments. In situ hybridization showed ODC messenger ribonucleic acid (mRNA) to be absent in kidneys of untreated females but abundant in the cortex and the outer stripe of the outer medulla of testosterone-treated female mice. The whole proximal tubule contained a great density of silver grains corresponding to ODC mRNA. In conclusion, no basal ODC activity was found in the nephron of female mice. The testosterone-inducible ODC is localized mainly in the proximal tubule, but is also present in distal tubules and collecting ducts. OAT is distributed along the whole nephron, but its activity is higher in proximal tubules than in distal tubules.},
  author       = {Levillain, O and Diaz, J J and Reymond, I and Soulet, Denis},
  issn         = {0031-6768},
  language     = {eng},
  number       = {5},
  pages        = {761--769},
  publisher    = {Springer},
  series       = {Pflügers Archiv},
  title        = {Ornithine metabolism along the female mouse nephron: localization of ornithine decarboxylase and ornithine aminotransferase},
  url          = {http://dx.doi.org/10.1007/s004240000340},
  volume       = {440},
  year         = {2000},
}