An adrenal gland hormone that instructs nephrons to increase reabsorption of salt and water, helping to raise blood pressure, is .

Aldosterone is released by the adrenal cortex and signals the kidney nephrons to reabsorb more sodium; water follows the sodium, increasing blood volume and helping raise blood pressure. ADH also increases water reabsorption, but it is made in the hypothalamus and released by the posterior pituitary, rather than being an adrenal hormone.

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