Parameters describing baroreflex control of SSNA and LSNA after bilateral microinjection of NMU (100 pmol) in the RVLM
Values are mean ± S.E. (n = 4–5). Maximum gain is the slope of the sigmoid curve of best fit at the MAP corresponding to steepest part of the curve.
| Lower Plateau | Upper Plateau | Midpoint | Maximum Gain | Range of SNA | Threshold Level | Saturation Level | Operating Range | |
|---|---|---|---|---|---|---|---|---|
| % | mm Hg | %/mm Hg | % | mm Hg | ||||
| SSNA | ||||||||
| Control | 14.6 ± 1.7 | 108.3 ± 4.8 | 127.3 ± 2.4 | −1.4 ± 00.07 | 93.7 + 5.0 | 76.4 ± 3.3 | 178.3 ± 4.1 | 101.9 ± 5.7 |
| NMU, excitatory phase | 28.8 ± 2.9** | 149.9 ± 14.5* | 138.4 ± 9.4 (N.S.) | −2.9 ± 0.2** | 121.1 ± 12.6* | 108.0 ± 9.3 (N.S.) | 168.9 ± 9.7 (N.S.) | 60.9 ± 3.1** |
| NMU, inhibitory phase | 19.9 ± 2.8 (N.S.) | 117.4 ± 11.4 (N.S.) | 136.6 ± 10.8 (N.S.) | −1.5 ± 0.2 (N.S.) | 97.4 ± 12.7 (N.S.) | 89.6 ± 9.9 (N.S.) | 183.7 ± 17.4 (N.S.) | 94.2 ± 18.4 (N.S.) |
| LSNA | ||||||||
| Control | 16.9 ± 8.1 | 97.4 ± 10.1 | 139.7 ± 12.2 | −2.3 ± 0.5 | 80.5 ± 9.1 | 111 ± 12.4 | 168.4 ± 13.3 | 57.4 ± 7.9 |
| NMU, excitatory phase | 19.2 ± 7.0 (N.S.) | 158 ± 9.2* | 136.3 ± 12.6 (N.S.) | −1.7 ± 0.4** | 138.9 ± 10.5* | 73.7 ± 16* | 198.9 ± 12.9** | 125.2 ± 14.3** |
| NMU, inhibitory phase | 19.5 ± 9.1 (N.S.) | 113.4 ± 27.3 (N.S.) | 138.5 ± 9.6 (N.S.) | −1.2 ± 0.5* | 93.9 ± 32.3 (N.S.) | 84 ± 6.2 (N.S.) | 193 ± 15.9* | 109 ± 14.7** |