ADH (Vasopressin) – ADH has an antidiuretic action that prevents the production of dilute urine.
Formation of urine = in the DCT and collecting ducts, water movement out of the body is regulated by ADH.
Stimulus for their release = lowered blood pressure or low salt or water concentration in the blood will stimulate the release of ADH from the posterior pituitary.
Actions (decrease/increase GFR) = increased ADH would decreases the GFR and a decrease in ADH would increase GFR.
Dilute/Concentrated Urine Results = if there is a high amount of ADH, water moves out and will produce concentrated urine and if ADH is absent water will not be reabsorbed and will produce dilute urine.
Stimulus for their release = if blood pressure drops dramatically this will trigger renin secretion from the JG cells, renin acts on angiotensinogen to form angiotensin I, angiotensin I is converted to angiotensin II therefore angiotensin II causes mean arterial pressure to rise and stimulates the adrenal cortex to release aldosterone. As a result, both systemic and glomerular hydrostatic pressure rises.
Actions (decrease/increase GFR) = the efferent arteriole constricts, forcing blood to build up in the glomerulus, which maintains the GFR. The activation of the RAAS causes a decrease in GFR.
Dilute/Concentrated Urine Results = activation of the Renin-Angiotensin-Aldosterone System will result in concentrated urine results.
Atrial Naturetic Pepetide (ANP) Hormone
Stimulus for their release = large increase in blood volume promotes release of ANP.
Actions = result is more urinary output, less blood volume and decreased blood pressure. GFR will increase with the release of ANP.
Dilute/Concentrated Urine Results = urine will be