Classification Term: 170198

18-Hydroxycorticosterone

C21H30O5 (362.209313)

18-Hydroxycorticosterone is a corticosteroid and a derivative of corticosterone. If it is present in sufficiently high concentrations, it can lead to serious electrolyte imbalances (an electrolyte toxin). 18-Hydroxycorticosterone serves as an intermediate in the synthesis of aldosterone by the enzyme aldosterone synthase in the zona glomerulosa. Chronically high levels of 18-hydroxycorticosterone are associated with at least three inborn errors of metabolism including adrenal hyperplasia type V, corticosterone methyl oxidase I deficiency, and corticosterone methyl oxidase II deficiency. Each of these conditions is characterized by excessive amounts of sodium being released in the urine (salt wasting), along with insufficient release of potassium in the urine, usually beginning in the first few weeks of life. This imbalance leads to low levels of sodium and high levels of potassium in the blood (hyponatremia and hyperkalemia, respectively). Individuals with corticosterone methyloxidase deficiency can also have high levels of acid in the blood (metabolic acidosis). Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). The hyponatremia, hyperkalemia, and metabolic acidosis associated with corticosterone methyloxidase deficiency can cause nausea, vomiting, dehydration, low blood pressure, extreme tiredness (fatigue), and muscle weakness. 11 beta,18,21-Trihydroxypregn-4-ene-3,20-dione. 18-Hydroxycorticosterone is a derivative of corticosterone. It serves as an intermediate in the synthesis of aldosterone by the enzyme aldosterone synthase in the zona glomerulosa. [HMDB] D006730 - Hormones, Hormone Substitutes, and Hormone Antagonists > D006728 - Hormones