Amplitude and frequency characteristics of sympathetic nerve discharge in normotensive rats

: Electrical discharges in the cervical sympathetic trunk and arterial blood pressure were recorded in chloralose-anaesthetized Wistar rats. Some experiments were performed in rats with impaired baroreceptor reflex. The efferent electrical activity was analysed in amplitude and frequency domain. It has been shown that arterial and cardio-pulmonary mechanoreceptors do not affect magnitude of the electrical activity. However, arterial and cardio-pulmonary baroreceptor reflex arc seems to be involved in frequency modulation of the efferent sympathetic activity.