Fig. 6
From: The relationship between aortic baroreceptor activity and arterial pressure is not monotonic
Record of two type D baroreceptors. The frequency of the larger unit is shown in the bottom trace. At low pressures (left of A) both receptors fired during diastole. At A, the larger unit began firing during systole, while the smaller unit continued to fire during diastole. P th for the larger unit is the pressure at A, while P th for the smaller unit is the pressure at B. From their respective P th values each fibre showed an increase in firing rate with increasing pressure. The mean discharge for the larger unit was identical at the lowest and highest pressures shown in this figure (six action potentials per cycle)