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Updated: Aug 14, 2026

Visualization of Endoplasmic Reticulum Localized mRNAs in Mammalian Cells
Published on: December 17, 2012
[Role of endoplasmic reticulum in the secretion of prolactin (author's transl)]
Abstract:
Thyroliberin (TRH) exerts a biphasic effect on the secretion of prolactin. It involves first a rapid release of a previously formed hormonal pool and then a long term delayed effect on hormone synthesis. Ultrastructural immunocytochemistry has permitted to visualize the prolactin content of the endoplasmic reticulum and to follow the transit of secretory product during TRH induced acute release in GH3 cells and in normal prolactin cells in primary culture. After 30 min, 1 hr of action, TRH induces a decrease in the prolactin content of the endoplasmic reticulum followed after 2 hrs by a reloading of this compartment. These immunocytochemical observations offer a morphological correlate to previous biochemical studies on the biphasic effect of TRH.
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