04/01/2018 · The Biosynthesis of Prolactin
Prolactin - Colorado State University
The rates of synthesis and release of growth hormone (GH), prolactin, and whole protein of the rat anterior pituitary were determined using an method.
1. Thyroidectomy caused a marked decrease in both synthesis and release of GH. Decreased synthesis was restored by a single injection of T3 (20μg/100g body weight) within 12hr. Decreased GH release was also increased gradually by T3 injection. The percentage release of GH was increased by thyroidectomy and the increase was depressed by T3 injection.
2. Prolactin synthesis was increased by thyroidectomy, and the increased synthesis was suppressed as early as 3 hr after T3 injection. Prolactin release was not affected by thyroidectomy. The percentage release decreased significantly after thyroidectomy.
3. Whole protein synthesis was increased by thyroidectomy and the increase was suppressed by T3 injection. The whole protein release and the percentage release were not influenced by thyroidectomy and decreased significantly within 3 hr after T3 injection.
4. Added , T3 had no effect on synthesis of whole pituitary protein, but whole protein release was clearly suppressed at concentrations as low as 10-7m.
These results indicated that thyroid hormone stimulated GH synthetic processes and depressed GH release processes. Prolactin synthetic processes were depressed by thyroid hormone. The mechanisms of the thyroid hormone action and the physiological significance of the facts observed are discussed.
Effects of prostaglandins on prolactin and growth …
In summary, the results of this investigation demonstrate that PRL substantially down-regulates the expression of the abundant 37, 000 MW protein(s) in the corpus luteum.
Prolactin: Synthesis, Fate and Actions | SpringerLink
The synthesis of anterior pituitary proteins was examined in a double label experiment in which pituitaries from ovariectomized, female rats were incubated with [14C]leucine and pituitaries from rats receiving estradiol injections were incubated with [3H]leucine.