The different hormones present on the renal tubule concern renin with low blood pressure where it is released by the kidneys and creates angiotensin II to stimulate the adrenal cortex to release aldosterone. Aldosterone promotes the reabsorption of salt and water, decreases urine volume and increases blood pressure. Antidiuretic hormone (ADH) is dehydrated and causes the release of ADH which then stimulates the reabsorption of water in the collecting ducts. Atrial natriuretic peptide (ANP) promotes the excretion of water and salt in response to elevated blood pressure, increased urine volume and decreased blood volume result in decreased blood pressure. Parathyroid hormone (PTH) increases blood calcium by increasing calcium absorption in the kidneys. It also causes the release of calcium from the bones and stimulates the production of vitamin D in the bones