Fig. 3. Representative hypertensive baroreflex responses at (A) 70%, (B) 80% and (C) 90% of development after an injection of 120 µg kg^–1 of phenylephrine (the highest dose). The time of injection is indicated by the arrow. While the y-axis absolute scales vary between developmental ages, the relative scales are maintained for comparative purposes. a, arterial pressure; f_H, heart rate.