Table 2.
Cough-related variables before and 15 min after bilateral microinjections of clonidine into the cVRG (n = 6)
| CN | TT (sec) | TI, (sec) | TE (sec) | PPA (RU) | PAA (RU) | |
|---|---|---|---|---|---|---|
| Mechanical stimulation | ||||||
| Control | 3.5 ± 0.23 | 0.62 ± 0.01 | 0.37 ± 0.01 | 0.24 ± 0.01 | 0.62 ± 0.02 | 0.59 ± 0.02 |
| 0.5 mmol/L clonidine | 2.0 ± 0.25** | 0.74 ± 0.03* | 0.39 ± 0.01 | 0.35 ± 0.03* | 0.57 ± 0.03 | 0.41 ± 0.03* |
| 5 mmol/L clonidine | − | − | − | − | − | − |
| Citric acid inhalation | ||||||
| Control | 4.7 ± 0.42 | 0.51 ± 0.01 | 0.35 ± 0.01 | 0.16 ± 0.01 | 0.57 ± 0.02 | 0.58 ± 0.01 |
| 0.5 mmol/L clonidine | 2.5 ± 0.22** | 0.71 ± 0.04* | 0.43 ± 0.01* | 0.27 ± 0.03* | 0.51 ± 0.03 | 0.32 ± 0.05** |
| 5 mmol/L clonidine | − | − | − | − | − | − |
Values are means ± SEM; n, number of animals; CN, cough number; TT, cycle duration; TI, inspiratory time; TE, expiratory time; PPA, peak phrenic activity in relative units (RU); PAA, peak abdominal activity in relative units (RU). Negative marks indicate the absence of cough responses. *P < 0.05; **P < 0.005 compared with control cough.