Stability of adrenocorticotropic hormone (ACTH) and pathways of deamidation of asparaginyl residue in hexapeptide segments.

Abstract

Adrenocorticotropic hormone (corticotropin or ACTH), secreted by the anterior pituitary, stimulates the adrenal cortex to produce and secrete Cortisol, corticosterone, aldosterone, and a number of weakly androgenic substances by activating adenyl cyclase in the cell membranes (Haynes and Larner, 1975). The activity of ACTH is destroyed by the proteolytic enzymes of the gastrointestinal tract; therefore, the hormone is ineffective when given orally. It is readily absorbed from parenteral sites and is usually administered by intramuscular injection and occasionally by intravenous infusion (Haynes and Larner, 1975). ACTH rapidly disappears from the circulation following its intravenous administration in man; the plasma half-life is about 15 min. No significant biological activity is present in the urine (Haynes and Larner, 1975).