| Popis: |
The pituitary is an endocrine organ consisting functionally of an anterior lobe and a posterior lobe. The anterior lobe secretes six hormones (prolactin, adrenocorticotrophic hormone, thyroid-stimulating hormone, the gonadotrophic hormones: luteinizing hormone and follicle-stimulating hormone, and growth hormone). The posterior lobe secretes antidiuretic hormone, also known as arginine vasopressin, and oxytocin. Pituitary hormones are secreted via complex regulatory control mechanisms, which may include stimulatory or inhibitory effects from hypothalamic-releasing hormones, influence from nonhypothalamic hormones produced remotely, or by systemic influences. Pituitary disease may involve decreased pituitary hormone secretion (hypopituitarism) or hypersecretion, either of which may be due to pituitary tumors. Endocrine dysfunction may be “secondary” (also called “central,” resulting from pituitary disease) or “primary” (where the dysfunction arises in the end-organ). The various endocrinopathies involving the pituitary are discussed, including the clinical features, diagnostic approach including clinical features and laboratory test strategies, pitfalls of inappropriate laboratory testing or interpretation, and pros and cons of various laboratory testing methodologies. |
