Table S1.Overall changes in systolic blood pressure (SBP) and heart rate (HR) of rats pretreated with 0.9% NaCl solution (Control, n=12), NO synthesis inhibitor alone (L-NAME, n=12), and superimposedhexamethonium (HEX+L-NAME, n=12) or guanethidine (GUA+L-NAME, n=12).

Control / Hex / GUA / L-NAME / HEX+L-NAME / GUA+L-NAME
PreCS / SBP
(mmHg) / 122.12±3.68 / 102.88±2.62a,b / 116.21±4.58a,c / 182.92±7.58a / 176.25±6.66a / 153.86±3.16a
HR
(beats/min) / 301.91±9.27 / 350.25±6.04a,b / 282.32±7.78a,c / 277.56±20.4a / 296.11±6.82a / 242.44±4.69a
CS / SBP
(mmHg) / 149.87±2.61# / 122.93±2.21#,b / 122.84±4.56c / 187.94±8.36a / 162.60±5.19a / 140.45±3.79#,a
HR
(beats/min) / 478.24±11.34# / 431.23±6.81#,a,b / 346.44±12.5#,c / 346.40±12.5#,a / 342.80±12.2#,a / 284.31±11.9#,a

Note:The effects of HEX alone (n=12) and GUA alone (n=12) on SBP and HR were reported in our previous report (gray shaded) [Fig. 3 in Chinese Journal of Physiology Vol. 58, No. 5. Liu, Y-P, Lin, Y-H, Lin, C-C, Lin, Y-C, Chen, Y-C, Lee, P-L,and Tung, C-S “Role of Efferent Sympathoadrenal Effects in Cooling-Induced Hemodynamic Perturbations in Rats: An Investigation by Spectrum Analysis”. pp. 312-321, Copyright 2015, with permission from the Chinese Journal of Physiology]. This is used for a better comparison with addition effects observed in the present study (i.e., HEX+L-NAME and GUA+L-NAME, respectively). CS, cold stress (4°C ice-water immersion of the palms and soles); PreCS, before CS; PostCS, after CS. Data represent means ± SE. #,p<0.05 compared the same parameter of CS toPreCS;a, p<0.05 comparedwith Control; b, p<0.05 compared with HEX+L-NAME; c,p<0.05 compared with GUA+L-NAME.

Table S2.Overall changes in average spectral powers for blood pressure variability (BPV) and heart rate variability (HRV)of rats pretreated with0.9% NaCl solution (Control, n=12), NO synthesis inhibitor alone (L-NAME, n=12), and superimposedhexamethonium (HEX+L-NAME, n=12) orguanethidine (GUA+L-NAME, n=12).

Blood Pressure Variability
Control / HEX / GUA / L-NAME / HEX+L-NAME / GUA+L-NAME
PreCS / VLF (mmHg2) / 1.33±0.41 / 1.18±0.3 / 0.61±0.17c / 2.43±1.13b / 0.75±0.24 / 1.32±0.24
LF (mmHg2) / 1.26±0.29 / 1.29±0.72 / 0.31±0.06a,c / 3.25±0.52b,c / 0.89±0.25 / 0.74±0.20a
HF (mmHg2) / 0.88±0.21 / 1.21±0.65 / 1.02±0.30 / 7.65±6.41a / 0.97±0.35 / 1.14±0.22
TP (mmHg2) / 6.76±1.68 / 7.59±3.15 / 3.66±0.81 / 8.64±2.53c / 8.03±1.79 / 3.38±0.92
CS / VLF (mmHg2) / 8.28±2.52# / 3.47±1.26#,a / 3.01±0.58#,a / 22.01±6.25#,a,b,c / 2.37±0.34#,a / 2.93±0.43#,a
LF (mmHg2) / 12.93±4.80# / 5.61±3.53 / 5.54±1.7#,c / 16.9±6.01#,b,c / 3.48±1.15# / 2.36±0.44#,a
HF (mmHg2) / 20.17±9.86# / 7.07±5.21 / 9.43±2.57 / 16.1±7.01c / 13.58±6.95#,c / 3.22±0.78a
TP (mmHg2) / 88.51±35.20# / 19.63±20.19# / 29.73±13.38# / 123.4±29.1#,c / 21.70±10.63a,c / 10.49±2.50#,a
Heart Rate Variability
Control / HEX / GUA / L-NAME / HEX+L-NAME / GUA+L-NAME
PreCS / VLF (ms2) / 15.86±3.21 / 2.05±0.7a,b / 16.84±10.1c / 24.45±5.76b / 2.7±1.55a,c / 9.07±1.74
LF (ms2) / 1.30±0.40 / 0.53±0.1 / 1.45±0.81 / 15.28±7.64a,b / 0.61±0.20c / 3.47±1.09a
nLF (n.u) / 0.07±0.01 / 0.02±0a / 0.02±0a / 0.09±0.03b,c / 0.03±0.01a / 0.04±0.01a
HF (ms2) / 6.77±1.01 / 6.86±1.35 / 10.91±2.09c / 57.51±21.15a,b / 8.64±2.6c / 55.61±21.55a
nHF (n.u) / 0.36±0.05 / 0.61±0.09a / 0.21±0.03a,c / 0.41±0.07b / 0.62±0.11a / 0.54±0.11a
LF/HF / 0.19±0.03 / 0.04±0.01a / 0.14±0.04c / 0.23±0.06c / 0.13±0.09 / 0.07±0.01a
TP (ms2) / 40.25±7.44 / 20.35±8.37a / 71.12±31.45 / 176.28±52.27a,b / 26.86±14.90 / 116.2±28.30a
CS / VLF (ms2) / 7.13±2.66 / 0.97±0.18#,a,b / 7.47±2.03c / 37.36±6.14#,a,b / 4.12±1.58c / 18.33±4.81#
LF (ms2) / 0.93±0.25 / 0.63±0.11 / 0.95±0.11c / 3.63±0.72a,b / 0.95±0.26c / 5.64±2.13a
nLF (n.u) / 0.07±0.01 / 0.04±0.01 / 0.04±0.01a / 0.04±0.01#,a / 0.03±0.01a / 0.04±0.01a
HF (ms2) / 5.04±1.32 / 8.04±1.73 / 17.78±4.30c / 39.48±10.10b / 13.7±5.10c / 64.05±24.62
nHF (n.u) / 0.33±0.05 / 0.56±0.02a / 0.51±0.09a / 0.36±0.08 / 0.5±0.09a / 0.4±0.11
LF/HF / 0.23±0.07 / 0.08±0.02a / 0.1±0.04a / 0.15±0.04 / 0.18±0.09 / 0.10±0.02a
TP (ms2) / 25.33±6.56 / 15.45±3.08b / 45.64±9.18a,c / 154.37±21.88a,b / 30±8.46c / 165.93±20.6a

Note: The effects of HEX alone (n=12) and GUA alone (n=12) on BPV and HRV described in our previous report (gray shaded) [Fig. 4 in Chinese Journal of Physiology Vol. 58, No. 5. Liu, Y-P, Lin, Y-H, Lin, C-C, Lin, Y-C, Chen, Y-C, Lee, P-L, and Tung, C-S “Role of Efferent Sympathoadrenal Effects in Cooling-Induced Hemodynamic Perturbations in Rats: An Investigation by Spectrum Analysis”. pp. 312-321, Copyright 2015, with permission from the Chinese Journal of Physiology]. This is used for a better comparison with addition effects observed in the present study (i.e., HEX+L-NAME and GUA+L-NAME, respectively).CS, cold stress (4°C ice-water immersion of the palms and soles); PreCS,before CS;PostCS, after CS; VLF,very low frequency; LF, low frequency; HF, high frequency; nLF, normalized low frequency;nHF, normalized high frequency; LF/HF, ratio; TP, total power. Data represent means ± SE. #,p<0.05 compared the same parameter of CS toPreCS;a, p<0.05 comparedwith Control; b, p<0.05 compared with HEX+L-NAME; c, p<0.05 compared with GUA+L-NAME.

1