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

It has previously been shown in the ewe that luteinizing hormone (LH)-containing secretory granules become polarized to the side of the gonadotrope nearest to a vascular sinusoid during the preovulatory period. We have used laser scanning confocal microscopy to monitor the migration of LH and follicle stimulating hormone (FSH)-containing secretory granules in the gonadotrope of the ewe. Ovariectomized (OVX) ewes (n = 4/group) were given either 50 micrograms of estradiol benzoate (EB) or oil and were killed 16 h later for collection of the pituitary glands for immunohistochemistry and confocal microscopy. Pituitary sections were simultaneously immunolabelled for LH and FSH and were visualized on the same sections using fluorescent markers. All cells that contained LH also contained FSH and vice versa. The results showed that LH-containing granules were uniformly distributed throughout the cytoplasm in 83% of gonadotropes from controls, while in the remaining 17% the granules were predominantly located adjacent to the plasma membrane. Following EB treatment, LH-containing secretory granules were distributed around the plasma membrane in 84% of immunopositive gonadotropes; FSH remained uniformly distributed throughout the cytoplasm. We conclude that estrogen causes the movement of LH-containing granules to the plasma membrane in gonadotropes but does not influence the distribution of FSH-containing granules. Rather than being polarized to one side of the cell, the LH-containing granules were distributed around the periphery of the cell.

The Positive Feedback Action of Estrogen Mobilizes LH-Containing, but not FSH-Containing Secretory Granules in Ovine Gonadotropes