Hormonal regulation by ADH and aldosterone You have probably noticed that urine is not always the same. The body is capable of adjusting the volume and the osmolarity of its urine output depending on a number of factors. The kidneys are regulated by hormones such as antidiuretic hormone (ADH) and aldosterone. These hormones are secreted in response to changes in the animal's internal water and salt balance. For example, sweating or blood loss can disrupt water and/or salt balance in the body, leading to a hormonal response that returns the system to homeostasis. Mechanisms for adjusting blood volume or osmolarity include increasing water and/or sodium reabsorption in the nephrons and collecting ducts. How do the what stimuli affect water and sodium (Na+) reabsorption in the kidneys?