Aldosterone
A steroid hormone produced by the adrenal cortex that regulates sodium and potassium balance and blood pressure. Aldosterone is part of the renin-angiotensin-aldosterone system (RAAS) and is relevant to understanding the broader hormonal context of metabolic peptide therapies.
Technical Context
Aldosterone is synthesised in the adrenal zona glomerulosa, regulated primarily by the renin-angiotensin system (angiotensin II stimulates aldosterone release) and serum potassium levels. It acts on mineralocorticoid receptors in the renal collecting duct to promote sodium reabsorption and potassium excretion, increasing blood volume and pressure. While aldosterone itself is not a peptide, the renin-angiotensin-aldosterone system involves the peptide angiotensinogen and its processing into angiotensin I and II. ACTH provides a secondary stimulus to aldosterone — this is why corticotropin/cosyntropin administration causes both cortisol and (to a lesser extent) aldosterone responses.