Nuclear estrogen and progesterone receptors in the oviduct of heifers under natural and superovulated estrous cycles

• Published in: Animal reproduction science Vol. 101; no. 1; pp. 28 - 37
• Main Authors: Valle, Guilherme Ribeiro, Cassali, Geovanni Dantas, Nogueira, José Carlos, Castro, Antônio Carlos Santana, Reis, Adelina Martha, Cardoso, Fábio Maurício, Figueiredo, Cláudia Beatriz Oliveira, Nascimento, Ernane Fagundes
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.09.2007
• Subjects: Animals; Bovine; Cattle; connective tissues; differential staining; epithelial cells; Estradiol - blood; Estrogen receptor; estrogens; Estrous cycle; Estrous Cycle - blood; Estrous Cycle - metabolism; Female; heifers; hormone receptors; immunohistochemistry; Male; muscle tissues; normal values; Oviduct; oviductal ampulla; oviductal isthmus; Oviducts - metabolism; Pregnancy; progesterone; Progesterone - blood; Progesterone receptor; Receptors, Estrogen - metabolism; Receptors, Progesterone - metabolism; superovulation; Superovulation - blood; Superovulation - metabolism; temporal variation; tissue analysis; Tissue Distribution; Estrogen receptor; Oviduct; Estrous cycle; Bovine; Progesterone receptor
• ISSN: 0378-4320; 1873-2232
• DOI: 10.1016/j.anireprosci.2006.08.026

Oviducts from 22 crossbred heifers were examined for the presence of nuclear estrogen (ERα) and progesterone (PR) receptors at different phases (estrus, metaestrus and diestrus) of naturally occurring estrous cycles and estrous cycles during which superovulation was induced. Receptors were detected by immunohistochemistry in the epithelial cells, connective tissue and muscular layer of oviductal infundibulum, ampulla, ampullary/isthmic transition and isthmus. Epithelial ERα was found along the entire oviduct regardless of the cycle phase and of the circulating concentrations of 17β-estradiol (E 2) and progesterone (P 4). Epithelial PR was found mainly at the ampullary-isthmic transition and isthmus and more intensely at the estrus phase but their amount was not correlated with P 4 concentrations. ERα in the connective tissue was more abundant at the infundibulum and ampulla, regardless of the phase of the estrous cycle and of E 2 and P 4 circulating concentrations. PR in the connective tissue was found mostly at the ampulla, regardless of the estrous cycle phase but no correlations were found between amount and P 4 concentrations. ERα staining intensity in the muscular layer was similar at all phases of the estrous cycle and at all anatomical segments of the oviducts. However, PR staining was more intense at the isthmus during the metaestrus phase and it was negatively correlated with P 4 concentrations. In general, data from the present research suggest that P 4 exerts an inhibitory role upon ERα and PR. Also, no differences were found between animals subjected or not to superovulation.