RÉSUMÉ
TRPV5 is believed to play an important role in the regulation of urinary calcium excretion. We assessed the effects of hydrochlorothiazide (HCTZ) on the expression of TRPV5, calbindin-D28K, and several sodium transporters in hypercalciuric rats. Sprague- Dawley rats were divided into 4 groups; control, HCTZ, high salt, and high salt with HCTZ group in experiment 1; control, HCTZ, high calcium (Ca), and high Ca with HCTZ group in experiment 2. To quantitate the expression of TRPV5, calbindin- D28K, and sodium transporters, western blotting was performed. In both experiments, HCTZ significantly decreased urinary calcium excretion. TRPV5 protein abundance decreased in all hypercalciuric rats, and restored by HCTZ in both high salt with HCTZ and high Ca with HCTZ group. Calbindin-D28K protein abundance increased in the high salt and high salt with HCTZ groups, but did not differ among groups in experiment 2. Protein abundance of NHE3 and NKCC2 decreased in all hypercalciuric rats, and were restored by HCTZ in only high Ca-induced hypercalciuric rats. In summary, protein abundance of TRPV5, NHE3, and NKCC2 decreased in all hypercalciuric rats. The hypocalciuric effect of HCTZ is associated with increased protein abundance of TRPV5 in high salt or calcium diet-induced hypercalciuric rats.
Sujet(s)
Animaux , Mâle , Rats , Transport biologique , Calcium/urine , Canaux calciques/composition chimique , Protéine G liant le calcium S100/biosynthèse , Hydrochlorothiazide/pharmacologie , Hypercalciurie/thérapie , Modèles biologiques , Rat Sprague-Dawley , Sodium/métabolisme , Antiport des ions sodium-hydrogène/composition chimique , Symporteurs des ions sodium-potassium-chlorure/métabolisme , Canaux cationiques TRPV/biosynthèse , Thiazides/pharmacologieRÉSUMÉ
Salt stress is an environmental factor that severely impairs plant growth and productivity. We have cloned a novel isoform of a vacuolar Na+/H+ antiporter from Pennisetum glaucum (PgNHX1) that contains 5 transmembrane domains in contrast to AtNHX1 and OsNHX1 which have 9 transmembrane domains. Recently we have shown that PgNHX1 could confer high level of salinity tolerance when overexpressed in Brassica juncea. Here,we report the functional validation of this antiporter in crop plant rice.Overexpression of PgNHX1 conferred high level of salinity tolerance in rice. Transgenic rice plants overexpressing PgNHX1 developed more extensive root system and completed their life cycle by setting flowers and seeds in the presence of 150 mM NaCl. Our data demonstrate the potential of PgNHX1 for imparting enhanced salt tolerance capabilities to salt-sensitive crop plants for growing in high saline areas.
Sujet(s)
Clonage moléculaire , Relation dose-effet des médicaments , Régulation de l'expression des gènes végétaux , Germination , Oryza/effets des médicaments et des substances chimiques , Pennisetum/génétique , Feuilles de plante/effets des médicaments et des substances chimiques , Végétaux génétiquement modifiés , Isoformes de protéines/composition chimique , Reproductibilité des résultats , Chlorure de sodium/pharmacologie , Antiport des ions sodium-hydrogène/composition chimiqueRÉSUMÉ
No abstract available.
Sujet(s)
Animaux , Isomérie , Salive/métabolisme , Antiport des ions sodium-hydrogène/métabolisme , Antiport des ions sodium-hydrogène/physiologie , Antiport des ions sodium-hydrogène/composition chimiqueRÉSUMÉ
No abstract available.