Background & Objective: Carotid baroreflex is the most important system of moment-by-moment control of blood pressure. In the past, in order to test carotid baroreflex, invasive methods were incorporated. In 1975 Eckberg introduced a non-invasive apparatus for testing carotid baroreflex sensitivity . The main objective of the present research was to design and construct a more progressive version of the Eckberg's model apparatus. This apparatus would be able to stimulate cervical baroreceptors through sucking the neck. This device will enable physiologists and pharmacologists to perform many researches about carotid baroreceptors.�

 Methods: In this apparatus advanced electronic and mechanical ciruits apply negative controlled pressure on the carotid sinus and increase the blood pressure. By application of negative pressure in front of neck, it stretches the soft cervical tissues including carotid sinus. One of the major modifications included was using resistant rubber instead of lead sheets for making the neck chamber. The whole system was controlled by a computer, which made our system more advanced as compared to the original model suggested by Eckberg. In order to test the apparatus, 12 young male volunteers received a -30mmHg to -90mmHg neck chamber pressure for 10 seconds. Any changes in cardiac cycles during the suction were being recorded using cardiopen II. So the charges could be evaluated.

 Results: The findings showed that stimulation of carotid baroreceptors increased the length of cardiac cycles abruptly. This increase is significantly different from the baseline( p<0.003) and shows the correct functioning of the equipment.

 Conclusion: The final tests confirmed the capability of the apparatus in stimulating carotid baroreceptors. This device can be used in other universities and research centers.