Human prolactin (hPRL) is a single chain polypeptide of 199 amino acids and a molecular weight of approximately 23,000 daltons. Its existence as a distinct chemical entity, separate from growth hormone, was established through a series of studies between 1965 and 1971. Prolactin is produced by the anterior pituitary and its secretion is regulated physiologically by inhibitory and releasing factors of the hypothalamus. Prolactin appears in the blood promptly after administration of thyrotropin-releasing hormone (TRH). The major physiologic action of prolactin is the initiation and maintenance of lactation in women.
Hyperprolactinemia has been established as a common cause of infertility and gonadal disorders in men and women. Prolactin has been shown to inhibit the secretion of ovarian steroids and to interfere with follicle
maturation and the secretion of LH and FSH in the human female. Measurement of elevated serum prolactin levels may provide the first quantitative evidence of pituitary dysfunction. Quantitation of prolactin levels is also of interest in the evaluation and management of patients with amenorrhea and galactorrhea.
Various factors other than disease states have been found to influence prolactin levels. Factors which increase prolactin concentrations include: pregnancy, breast stimulation, stress, coitus, administration of estrogens, progesterone, androgens, some psychotropic and antihypertensive drugs, and TRH. Factors which decrease prolactin concentrations include the administration of L-dopa and bromocriptine.
Manufacturer’s Reagent package insert Architect Prolactin, January 2016, Abbott Ireland Diagnostics Division, Lisnamuck, Longford Co.,Longford,Ireland