Transdifferentiation of Growth Hormone and Prolactin Secreting Cells
Until a decade ago, it was widely held that the growth hormone (GH)- producing somatotrophs and the prolactin (PRL)-secreting mammotrophs were separate and distinct cell types. This view began to change in 1985 with the publication of two papers by our group. In one of these, we characterized the ontogeny of GH- and PRL-secreting cells in fetal and neonatal rats and found that the appearance of GH secretors preceded that of PRL cells by about a week (1). In addition, we developed and utilized the sequential plaque assay to demonstrate that virtually all of the initial PRL secretors also released GH. This suggested that PRL secretors initially arose from a subset of traditional somatotrophs, and provided the first direct evidence that GH and PRL secretors could functionally interconvert.
KeywordsGrowth Hormone Pituitary Cell Plaque Assay Musk Shrew Reverse Hemolytic Plaque Assay
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