Table 1.

Cold pressor test responses

		1-min Cold Pressor Test		2-min Cold Pressor Test		3-min Cold Pressor Test		Two-way ANOVA
Cold Pressor Test	Baseline	30	60	90	120	150	180	Time	Trial	Time × Trial
Stroke volume, ml
Control	105 ± 15	105 ± 17	105 ± 20	104 ± 20	106 ± 21	106 ± 20	107 ± 19	0.450	0.296	0.450
Prazosin	112 ± 14	114 ± 15	111 ± 16	111 ± 16	110 ± 17	111 ± 17	112 ± 17
Cardiac output, l/min
Control	6.2 ± 1.3	6.6 ± 1.4	7.0 ± 1.6	6.6 ± 1.5	6.3 ± 1.4	6.3 ± 1.5	6.3 ± 1.4	0.200	0.049	0.021
Prazosin	6.7 ± 0.9	7.5 ± 1.3	7.5 ± 1.6	7.5 ± 1.4	7.6 ± 1.2	7.6 ± 1.1	7.6 ± 1.0
Heart Rate, beats/min
Control	59 ± 12	64 ± 11	67 ± 12	63 ± 13	61 ± 12	61 ± 13	59 ± 12	0.107	0.024	0.001
Prazosin	62 ± 12	68 ± 11	70 ± 13	70 ± 14	72 ± 14*	71 ± 12	70 ± 13*
Diastolic BP, mmHg
Control	79 ± 8	84 ± 9	91 ± 8*	92 ± 8	92 ± 9*	90 ± 8*	89 ± 8*	0.000	0.045	0.031
Prazosin	74 ± 9	76 ± 9	81 ± 10	82 ± 8*	83 ± 9	82 ± 9*	80 ± 8*
Systolic BP, mmHg
Control	133 ± 7	140 ± 11	148 ± 11*	150 ± 13	151 ± 12	149 ± 11*	148 ± 11*	0.000	0.169	0.023
Prazosin	131 ± 7	136 ± 7	141 ± 9	140 ± 6	141 ± 9	141 ± 9*	140 ± 7*
Rate pressure product
Control	7,927 ± 1,754	9,028 ± 1,804	9,901 ± 2,047	9,549 ± 2,097	9,212 ± 1,982	9,077 ± 2,011	8,834 ± 1,927	0.008	0.307	0.014
Prazosin	8,141 ± 1,534	9,284 ± 1,750	9,833 ± 2,023	9,858 ± 2,024	10,217 ± 2,204	9,941 ± 1,667*	9,826 ± 1,709*
LAD velocity max
Control	0.252 ± 0.03	0.325 ± 0.07	0.304 ± 0.03	0.280 ± 0.05	0.261 ± 0.04	0.266 ± 0.05	0.265 ± 0.05	0.007	0.769	0.594
Prazosin	0.261 ± 0.04	0.312 ± 0.04	0.302 ± 0.07	0.281 ± 0.06	0.278 ± 0.06	0.284 ± 0.06	0.279 ± 0.05
LAD velocity mean
Control	0.201 ± 0.03	0.256 ± 0.07	0.232 ± 0.03	0.224 ± 0.04	0.209 ± 0.03	0.215 ± 0.03	0.207 ± 0.03	0.041	0.603	0.400
Prazosin	0.199 ± 0.03	0.25 ± 0.02	0.226 ± 0.03	0.228 ± 0.05	0.231 ± 0.04	0.231 ± 0.04	0.228 ± 0.04

Hemodynamic and coronary responses during Cold pressor test (full Supplemental Table, averaged per 10-s intervals, is available online at the Journal website). P values refer to 2-way repeated-measures ANOVAs for within-participant comparison (time), between-trial comparison, and the interaction time × trial. BP, blood pressure; LAD, left anterior descending (coronary artery).

^*Significant difference compared with baseline values, P < 0.05. Italicized values indicate significant difference (P < 0.05).