Regulation of cerebrovascular compliance compared with forearm vascular compliance in humans: a pharmacological study

Figures

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  Figure 1.. Representative blood pressure (BP), brachial artery blood velocity (BAv), and middle cerebral artery blood velocity (MCAv) waveforms from one individual in experiment 1 (A; phentolamine infusion), experiment 2 (B; glycopyrrolate infusion), and experiment 3 (C; nicardipine infusion).

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  Figure 2.. A: forearm vascular compliance (Ci) and cerebrovascular Ci before (control) and after phentolamine infusion (phentolamine) under baseline conditions. Inset: cerebrovascular Ci shown on a smaller scale. Means (SD) (error bars) and individual data (solid lines) are presented. A two-way repeated-measures ANOVA examined the effect of drug (control vs. phentolamine) and vascular bed (cerebral vs. forearm) on Ci (n = 10, 4 females). B: percent increase in forearm vascular Ci and cerebrovascular Ci with phentolamine. Means (solid line) and individual data are shown. A paired t test evaluated differences between the cerebral and forearm vascular beds in the increase of Ci with phentolamine (n = 10, 4 females).

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  Figure 3.. Vascular resistance (Ri) in the cerebral vascular bed and forearm vascular bed before (control) and after phentolamine infusion (phentolamine) under baseline conditions. Inset: cerebrovascular Ri shown on a smaller scale. Means (SD) (error bars) and individual data (solid lines) are presented. A two-way repeated-measures ANOVA examined the effect of drug (control vs. phentolamine) and vascular bed (cerebral vs. forearm) on Ri (n = 10, 4 females). **P < 0.01.

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  Figure 4.. A: forearm vascular compliance (Ci) and cerebrovascular Ci before (control) and after glycopyrrolate infusion (glycopyrrolate) under baseline conditions. Inset: cerebrovascular Ci shown on a smaller scale. Means (SD) (error bars) and individual data (solid lines) are presented. A two-way repeated-measures ANOVA examined the effect of drug (control vs. glycopyrrolate) and vascular bed (cerebral vs. forearm) on Ci (n = 9, 5 females). B: percent increase in forearm vascular Ci and cerebrovascular Ci with glycopyrrolate. Means (solid line) and individual data are shown. A paired t test evaluated differences between the cerebral and forearm vascular beds in the increase of Ci with glycopyrrolate (n = 9, 5 females). *P < 0.05; **P < 0.01.

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  Figure 5.. Vascular resistance (Ri) in the cerebral vascular bed and forearm vascular bed before (control) and after glycopyrrolate infusion (glycopyrrolate) under baseline conditions. Inset: cerebrovascular Ri shown on a smaller scale. Means (SD) (error bars) and individual data (solid lines) are presented. A two-way repeated-measures ANOVA examined the effect of drug (control vs. glycopyrrolate) and vascular bed (cerebral vs. forearm) on Ri (n = 9, 5 females).

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  Figure 6.. A: forearm vascular compliance (Ci) and cerebrovascular Ci before (control) and after nicardipine infusion (nicardipine) under baseline conditions. Means (SD) (error bars) and individual data (solid lines) are presented. A two-way repeated-measures ANOVA examined the effect of drug (control vs. nicardipine) and vascular bed (cerebral vs. forearm) on Ci (n = 14, 6 females). B: percent increase in forearm vascular Ci and cerebrovascular Ci with nicardipine. Means (solid line) and individual data are shown. A paired t test evaluated differences between the cerebral and forearm vascular beds in the increase of Ci with nicardipine (n = 14, 6 females). *P < 0.05.

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  Figure 7.. Vascular resistance (Ri) in the cerebral vascular bed and forearm vascular bed before (control) and after nicardipine infusion (nicardipine) under baseline conditions. Inset: cerebrovascular Ri shown on a smaller scale. Means (SD) (error bars) and individual data (solid lines) are presented. A two-way repeated-measures ANOVA examined the effect of drug (control vs. nicardipine) and vascular bed (cerebral vs. forearm) on Ri (n = 14, 6 females).