In dogs, renal denervation did not affect the diuretic action accompanied with renal hemodynamic chanties and inhibition of electrolytes reabsorption rates in renal tubules by methoxyverapamil infused into the vein or into a renal artery, while renal denervation blocked the antidiuretic action due to the decreased free water and osmolar clearances along with the reduced sodium amounts excreted in urine by methoxyverpamil infused into the carotid artery. These experimental results suggest that methoxyverapamil may cause diuresis by direct action in kidney but the antidiuretic action through central function mediated by renal nerves.