Disclosed herein are system and method for locating and identifying nerves innervating the wall of arteries such as the renal artery. The system identifies area on vessel wall innervated with nerves； provides indication on whether energy is delivered accurately to a targeted nerve； and provides immediate post-procedural assessment of the effect of energy delivered to the nerve. The method includes evaluating a change in physiological parameters after energy is delivered to arterial wall； and determining the type of nerve that the energy was directed to (sympathetic or parasympathetic or none) based on the evaluated results. The system includes at least a device (101) for delivering energy to the wall of blood vessel； sensor (103) for detecting physiological signals from a subject； and indicator (105) to display results obtained using said method. Also provided are catheters (2510, 2520) for performing the mapping and ablating functions.
