The Anti Diuretic Hormone (ADH) is a protein secreted by the pituitary gland, which conserves body water by reducing the output of water in urine; it does this by promoting the reabsorbtion of water back into the bloodstream from the second convoluted tubule and collection ducts by altering the permability of these tubles, resulting in more water moving back into the blood steam. Osmoreceptors in the brain detects a change in the osmotic concentration of the blood and send or stops sending ADH to act appropriately to restore normal water levels by adjusting the amount of water reabsorbed.
Aldosterone is a hormone that helps maintain the Sodium and Potassium ion balance in the blood. The concentration of these ions is proportional to the volume of the blood, when there is low concentration of these ions, the blood volume is low, and when these ions are in a high concentration, the blood volume is high. This is because the amount of ions alters the concentration gradient, if receptors detect that the blood volume is low they will promote the sending of Aldosterone to absorb more of these ions through the collecting ducts, thus changing to concentration gradient promoting the reabsorbtion of water increasing blood volume.
Thats wha ive got