This assay is used for the in vitro quantitative detection of prolactin (PRL) levels in human serum and plasma. Prolactin, a hormone produced by the anterior pituitary gland, consists of 198 amino acids with a molecular weight of 22–23 kDa. It exists in three forms in serum: the biologically active monomer (about 80%), the inactive dimer (5–20%), and the less active tetramer (0.5–5%). Prolactin primarily targets the mammary glands, promoting breast development and milk production, especially during pregnancy and lactation due to increased estrogen and progesterone levels. Elevated prolactin levels (hyperprolactinemia) can disrupt reproductive functions in both men and women, causing conditions such as amenorrhea, infertility, galactorrhea, and gynecomastia. Prolactin testing is also important when breast or pituitary tumors are suspected, and is commonly performed using immunofluorescence or chemiluminescence methods.
