Estrogen Receptor Levels in the Oviducts and Endometria of Cynomolgus Macaques during the Menstrual Cycle 1

Abstract

We sampled oviducts and endometria of 27 cynomolgus macaques during the menstrual cycle and measured the concentration of nuclear and cytoplasmic estrogen receptors in these tissues by exchange assay. We assessed the stage of the cycle by correlating serum estradiol (E2) and progesterone (P), as measured by radioimmunoassay, with the morphological condition of the ovaries, oviducts and endometrium of each animal. We have previously identified a series of oviductal stages that reflected the orderly sequence of cytological changes in the oviduct during the cycle, and we normalized receptor measurements to these stages. The amounts of nuclear and cytoplasmic estrogen receptor in both the oviduct and the endometrium were approximately twofold greater in the follicular phase than in the luteal phase. In the follicular phase, elevated receptor levels were associated with oviductal proliferation and differentiation, as well as with endometrial proliferation. During the luteal phase, lowered levels were correlated with atrophy and dedifferentiation in the oviduct, but with hypertrophy and progestational development in the endometrium. When the luteal phase of one cycle ends and the follicular phase of the next begins, it is a decline in serum P, not a rise in serum E2, that precedes the elevation in estrogen receptor level and the onset of proliferation in the oviduct and endometrium. Proliferation of the reproductive tract and elevations in nuclear estrogen receptor levels during the early follicular phase can therefore be viewed as consequences of the release of the system from antagonism by P.

The Macaque Endometrium, with Special Reference to the Cynomolgus Monkey (Macaca fascicularis)

“…Our results on endometrial and myometrial estrogen and progesterone receptor expression in natural cyclic cynomolgus monkeys very closely resemble those obtained for these receptors in natural cyclic animals (Brenner et al 1991) and ovariectomized female cynomolgus monkeys implanted subcutaneously with estradiol and subsequent progesterone implants (McClellan et al 1986;Okulicz et al 1990;West and Brenner 1983) and rhesus monkeys (Okulicz and Scarrell 1998;. The observation that some cells within the epithelium lining the most basal portions of the glands did not express the estrogen receptor is supported by the results obtained by McCllellan et al (1986).…”

Ciliary Beating Plane and Wave Propagation in the Bovine Oviduct

“…Oviduct cells have also been shown not only to express estrogen and progesterone receptors but to do so in a cycle-dependent manner [Kenngott et al, 2011;Saruhan et al, 2011]. Furthermore, the cytosolic and nuclear levels of estradiol are higher during the follicular than the luteal phase [West and Brenner, 1983;Derussi et al, 2012] and hormonal status seems to affect ciliary movement [Nishimura et al, 2010]. Despite these effects of endocrine signals on ciliogenesis and ciliary activity, a reversal of mucociliary transport, i.e.…”

Hormonal regulation and localization of estrogen, progestin and androgen receptors in the endometrium of nonhuman primates: effects of progesterone receptor antagonists

“…For instance, classic binding studies (West and Brenner, 1983) and ICC (McClellan et al, 1986) indicate that total ER levels are minimal at the end of the secretory phase of the cycle, and increase >3 fold by the end of the LFT, 4 days after P withdrawal in the presence of E 2 and very strong ER staining can be detected in the glands and stroma after 14 days of E 2 alone (Fig. 9).…”