Design and implementation of a system for measurement and control of blood pressure with charge balanced current pulses to stimulate the carotid sinus nerve

It is well known that arterial baroreceptor reflex function is impaired in human spontaneous hypertension and in experimental hypertension. Therefore, a system consists of nerve stimulator and a real time blood pressure recorder has been designed and characterized for investigating the effect of carotid sinus nerve stimulating in drug-resistant hypertension studies. Blood pressure signals were successfully analyzed in system and systolic/diastolic/mean arterial pressure were displayed on LCD. The stimulator could deliver precise trains of asymmetric biphasic current pulses using a Howland Current Source, with regulated electrode bias-voltage for safe neural stimulation, to the electrodes. we considered all patterns of electrical pulses as fix parameters and only changes in frequency have been discussed in this work (amplitude of positive phase I
_OUT+
= +1mA, amplitude of negative phase I
_OUT-
= -250μA, duration of positive phase T = 200mS). We applied the system to seven normal anesthetized Wistar rats. The designed system successfully measured and decreased MAP in all rats. The present study laid a foundation for using a charge balanced current source to stimulate CSN and decrease blood pressure.