Ovarian steroids regulate tachykinin and tachykinin receptor gene expression in the mouse uterus.
BACKGROUND
In the mouse uterus, pregnancy is accompanied by changes in tachykinin and tachykinin receptor gene expression and in the uterotonic effects of endogenous tachykinins. In this study we have investigated whether changes in tachykinin expression and responses are a result of changes in ovarian steroid levels.


METHODS
We quantified the mRNAs of tachykinins and tachykinin receptors in uteri from ovariectomized mice and studied their regulation in response to estrogen and progesterone using real-time quantitative RT-PCR. Early (3 h) and late (24 h) responses to estrogen were evaluated and the participation of the estrogen receptors (ER), ERalpha and ERbeta, was analyzed by treating mice with propylpyrazole triol, a selective ERalpha agonist, or diarylpropionitrile, a selective agonist of ERbeta.


RESULTS
All genes encoding tachykinins (Tac1, Tac2 and Tac4) and tachykinin receptors (Tacr1, Tacr2 and Tacr3) were expressed in uteri from ovariectomized mice. Estrogen increased Tac1 and Tacr1 mRNA after 3 h and decreased Tac1 and Tac4 expression after 24 h. Tac2 and Tacr3 mRNA levels were decreased by estrogen at both 3 and 24 h. Most effects of estrogen were also observed in animals treated with propylpyrazole triol. Progesterone treatment increased the levels of Tac2.


CONCLUSIONS
These results show that the expression of tachykinins and their receptors in the mouse uterus is tightly and differentially regulated by ovarian steroids. Estrogen effects are mainly mediated by ERalpha supporting an essential role for this estrogen receptor in the regulation of the tachykinergic system in the mouse uterus.
Pinto
Francisco M
FM
Instituto de Investigaciones Químicas, CSIC, Sevilla, Spain. Francisco.pinto@iiq.csic.es
Pintado
C Oscar
CO
Pennefather
Jocelyn N
JN
Patak
Eva
E
Candenas
Luz
L
D000818:Animals; D004958:Estradiol / Q000502:physiology*; D047628:Estrogen Receptor alpha / Q000819:agonists; D005260:Female; D015870:Gene Expression; D051379:Mice; D009570:Nitriles / Q000494:pharmacology; D010053:Ovary / Q000378:metabolism / Q000502:physiology*; D010636:Phenols; D011374:Progesterone / Q000502:physiology*; D011422:Propionates / Q000494:pharmacology; D011720:Pyrazoles / Q000494:pharmacology; D018039:Receptors, Tachykinin / Q000235:genetics*; D015320:Tachykinins / Q000235:genetics*; D014599:Uterus / Q000378:metabolism*
C486182:2,3-bis(4-hydroxyphenyl)-propionitrile; D047628:Estrogen Receptor alpha; D009570:Nitriles; D010636:Phenols; D011422:Propionates; D011720:Pyrazoles; D018039:Receptors, Tachykinin; D015320:Tachykinins; C486184:4,4',4''-(4-propyl-((1)H)-pyrazole-1,3,5-triyl) tris-phenol; D011374:Progesterone; D004958:Estradiol