Aldosterone - activity mechanism and physiological role

In this article the main factors stimulating biosynthesis and aldosterone secretion through the adrenal cortex cells have been discussed: i.e. the renin-angiotensin system, potassium, sodium and ACTH concentration in blood plasma. Aldosterone is a type of steroid hormone that acts primarily in renal collecting ducts to stimulate resorption of Na+ as well as secretion of K+ and H+, Its connections with intracellular receptors stimulate the manifestation of several genes in the nucleus. Transcription and subsequent translation result in the production of new proteins which modulate ionic transport systems located in the apical and basolateral membranes in the principal and intercalated cells of the collecting tubules. The early phase of aldosterone action corresponds with the activation of preexisting ionic channels and pumps, while the late phase corresponds with the synthesis of new channels proteins and new Na+-K+-ATPase units. The peculiar character of aldosterone activity in the neonatal period at people and chosen animal species has also been treated in this paper.