prolactin in serum
Indications
- evaluation of hyperprolactinemia
- evaluation of galactorrhea, amenorrhea & infertility
Reference interval
Principle
Prolactin is a solid phase two-site immunoradiometric assay. Samples containing prolactin are reacted with a plastic bead (solid phase) coated with a monoclonal antibody directed toward a unique site in the prolactin molecule & with a radiolabeled monoclonal antibody directed against a distinctly different antigenic site on the same prolactin molecule.
Following the formation of the solid phase/prolactin/labeled antibody sandwich, the bead is washed to remove unbound labeled antibody. The solid phase is measured with a gamma counter. The amount of radioactivity measured is directly proportional to the concentration of prolactin present in the test sample.
Ab-1. (solid phase)__PROLACTIN__Ab-2 (radiolabeled Ab.)
Clinical significance
Prolactin or lactogenic hormone is a single chain polypeptide hormone secreted from the anterior pituitary gland. Prolactin's major function is to act in conjunction with a variety of other hormones to promote breast development & to initiate lactation in women. Presently, there is no known physiological function in men.
Measurements of serum prolactin is an essential part of the routine investigation of disorders of reproduction & puberty or suspected hypothalamic-pituitary dysfunction. Disorders in prolactin secretion are associated with hyperprolactinemia, which may result form prolactin secreting microadenomas, hypothalamic- pituitary dysfunction & a variety of drugs. Increased serum prolactin concentrations may produce galactorrhea, amenorrhea & infertility. Hyperprolactinemia also may be observed in patients with irritative chest wall lesions, hypothyroidism, ectopic production by malignant tumors, renal failure & post-ictal.
Serum prolactin is of no value in distinguishing seizure from vasovagal syncope.[6]
Increases
Specimen
- The determination of Prolactin should be performed on serum. Collect blood sample in a red-top venipuncture tube & allow blood to clot. Centrifuge the sample & separate from cells.
- If assay is performed within 24 hours after collection, the specimen should be stored in the refrigerator at 2-8 C. If the testing will be delayed more than 24 hours, the specimen should be frozen. Mix thoroughly after thawing to ensure consistency in the results. Avoid repeated freezing & thawing.
- Specimens showing particulate matter, erythrocytes, or turbidity should be centrifuged before testing.
More general terms
More specific terms
Additional terms
Component of
References
- ↑ Hybritech Incorporated. San Diego, CA. October, 1988.
- ↑ Prolactin Laboratory Test Directory ARUP: http://www.aruplab.com/guides/ug/tests/0020765.jsp
- ↑ Prolactin Laboratory Test Directory ARUP: http://www.aruplab.com/guides/ug/tests/0070115.jsp
- ↑ TRH Stim Prolactin 0 Min Laboratory Test Directory ARUP: http://www.aruplab.com/guides/ug/tests/0070116.jsp
- ↑ TRH Stim Prolactin 90 Min Laboratory Test Directory ARUP: http://www.aruplab.com/guides/ug/tests/0070119.jsp
- ↑ 6.0 6.1 Lusic I et al Serum prolactin levels after seizure and syncopal attacks. Seizure. 1999 Jun;8(4):218-22. PMID: https://www.ncbi.nlm.nih.gov/pubmed/10452919