Figure 1.
Arteriolar responses to α1R activation at five arteriolar orders
Top: percentage change in arteriolar constriction (from baseline) for five arteriolar orders (1A through 5A, n = 8–17 arterioles) at increasing concentrations (m) of PE. Data presented as the mean ± SEM. *Statistically different from 1A; #statistically different from 2A; †statistically different from 3A; §statistically different from 4A (all P < 0.05). Constriction responses to peak concentrations of PE were blocked by prazosin (% indicates the difference between responses with and without antagonist at PE 10−4 m, P < 0.05) for all orders. Bottom: normalized constriction responses fit to sigmoids. LogEC50 values are reported for each arteriolar order. LogEC50 values for 2A and 3A were greater than 4A and 5A (P < 0.05).