Arfalasin or Hoe 409, an angiotensin II (AII) blocker, inhibits the renin release thus delay recovery of urinary osmolality.

Angiotensin is a peptide hormone that causes vasoconstriction and a subsequent increase in blood pressure. It is part of the renin-angiotensin system, which is a major target for drugs that lower blood pressure. Angiotensin also stimulates the release of aldosterone, another hormone, from the adrenal cortex. Aldosterone promotes sodium retention in the distal nephron, in the kidney, which also drives blood pressure up. Angiotensin is an oligopeptide and is a hormone and a powerful dipsogen. Angiotensin I is derived from the precursor molecule angiotensinogen, a serum globulin produced in the liver. Angiotensin I is converted to angiotensin II (AII) through removal of two C-terminal residues by the enzyme angiotensin-converting enzyme (ACE), primarily through ACE within the lung (but also present in endothelial cells and kidney epithelial cells). ACE found in other tissues of the body has no physiological role (ACE has a high density in the lung, but activation here promotes no vasoconstriction, angiotensin II is below physiological levels of action). Angiotensin II acts as an endocrine, autocrine/paracrine, and intracrine hormone. Angiotensin II has prothrombotic potential through adhesion and aggregation of platelets and stimulation of PAI-1 and PAI-2. When cardiac cell growth is stimulated, a local (autocrine-paracrine) renin-angiotensin system is activated in the cardiac myocyte, which stimulates cardiac cell growth through protein kinase C. The same system can be activated in smooth muscle cells in conditions of hypertension, atherosclerosis, or endothelial damage. Angiotensin II is the most important Gq stimulator of the heart during hypertrophy, compared to endothelin-1 and α1 adrenoreceptors. Angiotensin II increases thirst sensation (dipsogen) through the subfornical organ of the brain, decreases the response of the baroreceptor reflex, and increases the desire for salt. It increases secretion of ADH in the posterior pituitary and secretion of ACTH in the anterior pituitary. It also potentiates the release of norepinephrine by direct action on postganglionic sympathetic fibers. Angiotensin II acts on the adrenal cortex, causing it to release aldosterone, a hormone that causes the kidneys to retain sodium and lose potassium. Elevated plasma angiotensin II levels are responsible for the elevated aldosterone levels present during the luteal phase of the menstrual cycle. Angiotensin II has a direct effect on the proximal tubules to increase Na+ reabsorption. It has a complex and variable effect on glomerular filtration and renal blood flow depending on the setting. Increases in systemic blood pressure will maintain renal perfusion pressure; however, constriction of the afferent and efferent glomerular arterioles will tend to restrict renal blood flow. The effect on the efferent arteriolar resistance is, however, markedly greater, in part due to its smaller basal diameter; this tends to increase glomerular capillary hydrostatic pressure and maintain glomerular filtration rate. A number of other mechanisms can affect renal blood flow and GFR. High concentrations of Angiotensin II can constrict the glomerular mesangium, reducing the area for glomerular filtration. Angiotensin II is a sensitizer to tubuloglomerular feedback, preventing an excessive rise in GFR. Angiotensin II causes the local release of prostaglandins, which, in turn, antagonize renal vasoconstriction. The net effect of these competing mechanisms on glomerular filtration will vary with the physiological and pharmacological environment. Angiotensin was independently isolated in Indianapolis and Argentina in the late 1930s (as 'angiotonin' and 'hypertensin', respectively) and subsequently characterised and synthesized by groups at the Cleveland Clinic and Ciba laboratories in Basel, Switzerland.

Aclerastide (DSC-127; NorLeu-3-A(1-7)) is an angiotensin analogue that is being developed by Derma Sciences (a subsidiary of Integra LifeSciences) for the treatment for wounds such as diabetic foot ulcer and surgical scars. The mechanisms of action include induction of progenitor proliferation, accelerated vascularization, collagen deposition, and re-epithelialization. Aclerastide recently failed in phase III clinical trials for treatment of diabetic foot ulcers. Phase I development of aclerastide ophthalmic solution is ongoing in the US.

Angiotensin (1-7) [Ang 1-7] is a 7 amino acid peptide generated predominantly from Ang II by the action of Ang-converting enzyme 2. Ang 1-7 can act as a negative modulator of aldosterone secretion in vitro and in vivo. The endogenous heptapeptide angiotensin-(1-7) (Ang-(1-7)) is a RAS component that has a central role in the alternative axis. It is generated by the cleavage of Ang-II by the action of the angiotensin converting enzyme 2 (ACE 2) and acts via interaction with the G-protein coupled receptor Mas. Angiotensin (1-7) induces vasorelaxation through release of NO and prostaglandins, perhaps through activation of a non-AT1, non-AT2 receptor, Mas. Counteracts the vasoconstrictive and proliferative effects of angiotensin II and stimulates vasopressin (anti-diuretic hormone) release in vivo. Clinical uses range from treatment of cardiovascular-related diseases, ocular pathologies, metabolic dysfunctions, brain conditions and degenerative diseases to applications in cell differentiation and hematopoiesis, tumor therapy, acute lung injury, fibrosis, infection, among others. Tarix Orphan is developing TXA127 for rare neuromuscular and connective tissue diseases. TXA127 is a pharmaceutical formulation of the naturally occurring peptide, Angiotensin (1-7). TXA127 has been effective in animal models of Duchenne muscular dystrophy (DMD), Limb-girdle muscular dystrophy (LGMD), congenital muscular dystrophy MDC1A, Marfan syndrome, and Dystrophic Epidermolysis Bullosa (DEB). FDA granted rare pediatric disease designation to TXA127 from Tarix to treat recessive dystrophic epidermolysis bullosa (RDEB). TXA127 has been granted orphan drug status by FDA as a treatment for pulmonary arterial hypertension, to enhance engraftment in patients receiving a stem cell transplant, and for Myelodysplastic Syndrome (MDS). Tarix Orphan has broad IP protection for TXA127 and Orphan Drug Designations (ODDs) have been granted for DMD LGMD and DEB in the U.S., and for DMD in Europe. Tarix Orphan aims to initiate a clinical trials for both DMD and DEB in early 2018 and has an active IND for a Phase II trial in DMD, as well as Fast Track designation for DMD.