Figure 4. Effects of pharmacological agents on the increases in the MBF and LBF on the left (ipsilateral) side evoked by left LN stimulation, and on the SABP.
Electrical stimulation was delivered (•) for 20 s with a supramaximal voltage of 20 V at 20 Hz using 2 ms pulses, before (control) and after (at 10 min) intravenous administration of hexamethonium (C6) at 1 and 10 mg kg−1 (A and B), atropine at 100 μg kg−1 (Atr; C), phentolamine at 100 μg kg−1 (Phe; D), and propranolol at 100 μg kg−1 (Pro; E). F, the MBF increases evoked by LN stimulation 10, 30 and 60 min after administration of C6 at 1 (white bars) and 10 (grey bars) mg kg−1, and Atr (black bars), are expressed as percentages of the pretreatment response and given as means ±s.e.m. The statistical significance of the differences in this pretreatment response (control) was assessed by ANOVA followed by a post hoc test (Fisher's PLSD) (**P < 0.01, ***P < 0.001).