Hyperosmotic NaCl and urea synergistically regulate the expression of the UT-A2 urea transporter in vitro and in vivo.
Biochem Biophys Res Commun
; 271(2): 368-73, 2000 May 10.
Article
en En
| MEDLINE
| ID: mdl-10799304
ABSTRACT
The UT-A2 urea transporter is involved in the recycling of urea through the kidney, a process required to maintain high osmotic gradients. Dehydration increases UT-A2 expression in vivo. The tissue distribution of UT-A2 suggested that hyperosmolarity, and not vasopressin, might mediate this effect. We have analyzed the regulation of UT-A2 expression by ambiant osmolarity both in vitro (mIMCD3 cell line) and in vivo (rat kidney medulla). The UT-A2 mRNA was found to be synergistically up-regulated by a combination of NaCl and urea. Curiously, the UT-A2 protein was undetectable in this hypertonic culture condition, or after transfection of the UT-A2 cDNA, whereas it could be detected in HEK-293 transfected cells. Treating rats with furosemide, a diuretic which decreases the kidney interstitium osmolarity without affecting vasopressin levels, led to decreased levels of the UT-A2 protein. Our results show that the UT-A2 urea transporter is regulated by hyperosmolarity both in vitro and in vivo.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas de Transporte de Membrana
/
Urea
/
Glicoproteínas de Membrana
/
Cloruro de Sodio
/
Proteínas Portadoras
Límite:
Animals
/
Humans
/
Male
Idioma:
En
Revista:
Biochem Biophys Res Commun
Año:
2000
Tipo del documento:
Article
País de afiliación:
Francia