Measurements of renal sympathetic nerve activity in conscious sinoaortic denervated rats.

The increase in renal sympathetic nerve activity (RSNA) produced in freely moving rats by sinoaortic denervation was analyzed both by counting the neural spikes and integrating the recorded electroneurogram. The percent increase was found to be greater when activity was calculated considering spike frequency (71%) rather than integrated voltage (54%). The different values obtained by the two methods suggests that after SAD, in addition to the increase in the nerve impulse frequency, there is an alteration in the pattern of nerve discharge.