What hormone dilates systemic arteries and increases blood flow to the kidneys causing urinary output?

The hormone responsible for dilating systemic arteries and increasing blood flow to the kidneys, thereby promoting urinary output, is atrial natriuretic peptide (ANP). ANP is released by the heart's atria in response to increased blood volume and pressure. It acts to reduce blood pressure by promoting vasodilation and enhancing sodium excretion, leading to increased urine production. This mechanism helps regulate fluid balance and blood pressure in the body.