What is the Origin of 11-Beta-Hydroxysteroid Dehydrogenase Type 2?

The term is derived from its chemical action as a hydroxysteroid dehydrogenase enzyme and its specific location on the steroid molecule at the 11-Beta position, with Type 2 designating its specific isoform. This enzyme is a key player within the broader system of steroid hormone metabolism and the endocrine regulation of the body's fluid and electrolyte balance. It is encoded by the HSD11B2 gene, placing its origin firmly within the realm of human genetic and physiological programming.

What is the Mechanism of 11-Beta-Hydroxysteroid Dehydrogenase Type 2?

The enzyme catalyzes the rapid and irreversible conversion of active cortisol into its biologically inactive metabolite, cortisone, directly within the cells expressing the mineralocorticoid receptor. By deactivating cortisol at this crucial site, it ensures that aldosterone, the dedicated mineralocorticoid, is the only hormone capable of binding to and activating the receptor. Impairment of this mechanism can lead to a state of apparent mineralocorticoid excess, characterized by hypertension and hypokalemia.

11-Beta-Hydroxysteroid Dehydrogenase Type 2 ∞ Area

11-Beta-Hydroxysteroid Dehydrogenase Type 2

Meaning

An enzyme, 11-Beta-Hydroxysteroid Dehydrogenase Type 2, is critically important for regulating the local activity of glucocorticoid hormones in mineralocorticoid-sensitive tissues, such as the kidney. Its primary function is to protect the mineralocorticoid receptor from being inappropriately activated by cortisol, which is a potent glucocorticoid that circulates at concentrations significantly higher than aldosterone. This enzymatic protection is essential for maintaining the delicate balance of electrolytes and ensuring proper blood pressure regulation.