English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Because pregnancy and estrogens both induce pituitary lactotroph hyperplasia, we assessed the expression of pituitary cell cycle regulators in two models of murine pituitary hyperplasia. Female mice were assessed during nonpregnancy, pregnancy, day of delivery, and postpartum. We also implanted estradiol (E(2)) pellets in female mice and studied them for 2.5 months. Pituitary weight in female mice increased 2-fold after E(2) administration and 1.4-fold at day of delivery, compared with placebo-treated or nonpregnant females. Pituitary proliferation, as assessed by proliferating cell nuclear antigen and/or Ki-67 staining, increased dramatically during both mid-late pregnancy and E(2) administration, and lactotroph hyperplasia was also observed. Pregnancy induced pituitary cell cycle proliferative and inhibitory responses at the G(1)/S checkpoint. Differential cell cycle regulator expression included cyclin-dependent kinase inhibitors, p21(Cip1), p27(Kip1), and cyclin D1. Pituitary cell cycle responses to E(2) administration partially recapitulated those effects observed at mid-late pregnancy, coincident with elevated circulating mouse E(2), including increased expression of proliferating cell nuclear antigen, Ki-67, p15(INK4b), and p21(Cip1). Nuclear localization of pituitary p21(Cip1) was demonstrated at mid-late pregnancy but not during E(2) administration, suggesting a cell cycle inhibitory role for p21(Cip1) in pregnancy, yet a possible proproliferative role during E(2) administration. Most observed cell cycle protein alterations were reversed postpartum. Murine pituitary meets the demand for prolactin during lactation associated with induction of both cell proliferative and inhibitory pathways, mediated, at least partially, by estradiol.

Estradiol Partially Recapitulates Murine Pituitary Cell Cycle Response to Pregnancy