Objective To investigate if ruthenium red( RR) possesses differentiating effects on baroreceptors and to understand the relationship between these different effects and types of the baroreceptors. Methods Carotid sinus-nerve preparation of the rabbit was perfused intrasinusally and extrasinusally in vitro. Baroreceptor discharges were recorded from nerve filaments containing 2-5 fibers while the intrasinusal pressure was clamped with pulsatile or ramp waves. Single fiber discharges were obtained by sorting ...