Figure 1. (Top) Changes in mean arterial blood pressure (MAP) during intravenous infusion of lidocaine. The MAP did not change in group C and vasopressor-SNP groups (groups E + SNP, N + SNP, P + SNP). The MAP significantly increased after 1 min of infusion in the hypertensive groups (groups E, N, P; P < 0.01), and there were no significant differences in the MAP among the three groups. (Bottom) Changes in heart rate (HR) during intravenous infusion of lidocaine. The HR in group C continuously decreased. The HRs significantly decrease after 1 min of infusion in the hypertensive groups (groups E, N, P; P < 0.01). The HRs in group E + SNP and N + SNP did not change. The HR in group P + SNP significantly decreased after 5 min of infusion (P < 0.01). Values are means plus/minus SD; n = 8. C - control (plain lidocaine); E = lidocaine with epinephrine; E + SNP - lidocaine with epinephrine + sodium nitroprusside; I.B.C. = immediately before convulsions; N = lidocaine with norepinephrine; N + SNP - lidocaine with norepinephrine + sodium nitroprusside; P = lidocaine with phenylephrine; P + SNP = lidocaine with phenylephrine + sodium nitroprusside.