ACTH (Adrenocorticotropic Hormone, Corticotropin)

Adrenocorticotropic hormone (ACTH), also known as corticotropin, is a polypeptide tropic hormone produced and secreted by the anterior pituitary gland. It is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological stress (along with its precursor corticotropin-releasing hormone from the hypothalamus). Its principal effects are increased production and release of corticosteroids. A deficiency of ACTH is a cause of secondary adrenal insufficiency and an excess of it is a cause of Cushing's disease. Pro-opiomelanocortin (POMC) is a precursor polypeptide with 241aa residues. It is synthesized by corticotrope cells of the anterior pituitary gland, melanotrope cells of the intermediate lobe of the pituitary gland, about 3000 neurons in the arcuate nucleus of the hypothalamus, and smaller populations of neurons in the dorsomedial hypothalamus and brainstem. The large molecule of POMC is the source of several important biologically active substances. POMC can be cleaved enzymatically into the following peptides: adrenocorticotrophic hormone (ACTH) and gamma LPH in the anterior pituitary gland CLIP, gamma LPH, gamma MSH and beta-endorphin in the intermediate lobe gamma-MSH met-enkephalin. Each of these peptides is packaged in large dense-core vesicles that are released from the cells by exocytosis in response to appropriate stimulation. gamma MSH produced by neurons in the arcuate nucleus has important roles in the regulation of appetite and sexual behavior, while alpha-MSH secreted from the intermediate lobe of the pituitary regulates the production of melanin. ACTH is a peptide hormone that regulates the secretion of glucocorticoids from the adrenal cortex. beta-endorphin and met-enkephalin are endogenous opioid peptides with widespread actions in the brain. Applications: Suitable for use in Immunohistochemistry. Other applications not tested. Recommended Dilution: Immunohistochemistry (paraffin): 1:50-1:100 Optimal dilutions to be determined by the researcher. Positive Control: Pituitary Cellular Localization: Cytoplasmic Storage and Stability: May be stored at 4 degrees C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20 degrees C. Aliquots are stable for 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.