Relationship between endothelin 1 and nitric oxide system in the corpus luteum regression.
The present study was designed to investigate the relationship between the nitric oxide (NO) system and endothelin 1 (ET-1) in the mechanism of corpus luteum (CL) development and consequently regression in rats. We first evaluated basal ET-1 levels in ovarian tissue from rats with different stages of CL development. An increased ovarian ET-1 content was found during CL regression. In a dose-department response, ET-1 decreased progesterone (P4) and increased prostaglandin (PG) PGF2alpha production. By means of a competitive nitric oxide synthase (NOS) inhibitor: L-nitro arginine methyl ester (L-NAME) and a slow NO releasing: diethyl-aminetriamine (DETA-NONOate), we demonstrated that NO system could be the intermediary in the ET-1 diminishing P4 production. The Western blot analysis revealed an increase on iNOS while eNOS protein expression was diminished. We also found a diminution of total NOS activity after ET-1 treatment. These data suggest the existence of a functional relationship between ET-1 and NOS isoforms leading the regulation of CL functionally.
Laboratorio de Fisiopatologi;a Ovárica, Centro de Estudios Farmacológicos y Botánicos (CEFYBO): Consejo Nacional de Investigaciones Cienti;ficas y Técnicas (CONICET), Serrano 669, (C1414DEM), Buenos Aires, Argentina.
T
T
Tognetti
A
A
Estevez
C G
CG
Luchetti
V
V
Sander
A M
AM
Franchi
A B
AB
Motta
D000818:Animals; D046508:Culture Techniques; D015237:Dinoprost / Q000378:metabolism*; D019332:Endothelin-1 / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000378:metabolism; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism; D003341:Luteolysis / Q000502:physiology*; D019331:NG-Nitroarginine Methyl Ester / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D010053:Ovary / Q000033:anatomy & histology / Q000378:metabolism*; D011374:Progesterone / Q000378:metabolism; D011555:Pseudopregnancy; D051381:Rats
D019332:Endothelin-1; D004791:Enzyme Inhibitors; D007527:Isoenzymes; D009569:Nitric Oxide; D011374:Progesterone; D015237:Dinoprost; D019001:Nitric Oxide Synthase; D019331:NG-Nitroarginine Methyl Ester