An "ardrenal" appears to be a typographical error or misspelling of "adrenal," which refers to the adrenal glands. These are small, triangular-shaped glands located on top of each kidney that produce hormones such as adrenaline, cortisol, and aldosterone, playing crucial roles in regulating metabolism, stress response, and blood pressure. If you meant something else by "ardrenal," please provide clarification!