Ovarian hormones modulate endothelin A and B receptor expression.
AIMS
The study aims to determine the modulatory roles of ovarian hormones, estrogen (E2) and progesterone (P), on the expression of endothelin A (ETA) and B (ETB) receptors in lung, liver and kidney tissues.


MAIN METHODS
Female Sprague-Dawley rats were subjected to bilateral ovariectomy and divided into four groups ovariectomized (OVX), OVX+E2, OVX+P, and OVX+E2+P. A separate group of rats underwent sham surgery and served as a control. Three weeks after OVX or sham surgery, tissues from lungs, liver, renal cortex, and inner medulla were collected, snap-frozen, and kept at -80°C for assessment of ETA and ETB receptor expression using real-time PCR.


KEY FINDINGS
E2-treated OVX animals had significantly lower expression of ETA receptors in the lungs, compared to OVX rats. Pulmonary ETB receptor mRNA was not measurably affected by any of the interventions. Hepatic ETA and ETB were significantly increased in OVX+E2+P rats, compared to sham rats. Renal inner medullary ETA and ETB receptor expressions were significantly elevated in OVX compared to sham, an effect that was prevented by co-supplementation of OVX with E2 and P. Additionally, both ETA and ETB receptor expression in the renal cortex were significantly attenuated by ovariectomy, and this reduction was not evident in OVX+E2 rats.


SIGNIFICANCE
These data suggest that ovarian hormones regulate ET receptor expression and may contribute to sex differences in cardiovascular and renal health.
['Gohar|Eman Y|EY|', 'Yusuf|Choudhury|C|', 'Pollock|David M|DM|']
D000818:Animals D004967:Estrogens D005260:Female D010052:Ovariectomy D010053:Ovary D011374:Progesterone D017207:Rats, Sprague-Dawley D044022:Receptor, Endothelin A D044023:Receptor, Endothelin B
Endothelin Estrogen Progesterone ET(A) receptors ET(B) receptors