Figure 1

Muscle sympathetic nerve traffic values (MSNA), expressed as burst incidence over time (bs min⁻¹, left panel) and as burst incidence corrected for heart rate (bs per 100 hb, right panel) in normotensive subjects (NT, normal clinical and ambulatory blood pressure), essential hypertensive patients (EHT, elevated clinical and ambulatory blood pressure) and white-coat hypertensive patients (WCHT, elevated clinical but normal blood pressure). Data are shown as the mean±s.e. Asterisks (*P<0.05, **P<0.01) refer to the statistically significant differences between groups. BP: blood pressure. Arrows indicate the normality (→) or elevation (↑) of clinical and ambulatory (24 h) blood pressure in the 3 groups of subjects. Figure created using data from Grassi et al.²¹