Treatment of kidney disease, conceptual illustration. The kidney is one of a pair of organs that form urine by filtering out waste products from the blood. The urine travels down the ureter to the bladder. On the kidney's top surface is the adrenal gland. This endocrine gland secretes a variety of hormones. These include adrenaline (epinephrine), the body's stress hormone. Adrenaline increases heart rate, breathing and metabolism to prepare the body for flight or fight. The adrenals also produce corticosteroid hormones which affect carbohydrate metabolism and the sex glands.