The subject of the present invention is sharp/blunt trocar for freezing tissues containing sealed channels for conducting refrigerant in a continuous flow, connected with a pump and a container for the refrigerant, terminating in a freezing head, wherein the freezing head possesses at least one elastic surface (2), which changes shape and distends as a result of pumping refrigerant under pressure through the trocar forming a decompression chamber (5), in which refrigerant undergoes decompression causing the elastic surface (2) of the freezing head to cool, and the aforementioned elastic surface (2) is capable of fitting itself to the tissue being subjected to freezing (3). The subject of the present invention is also a the use of a sharp/blunt trocar in the downregulation of arterial blood pressure in the renal artery.
