TY - JOUR
T1 - Inhibitory effects of propofol on neuron firing activities in the rostral ventrolateral medulla
AU - Yang, Ching Yue
AU - Tan, P. C.
AU - Wu, Wun Chin
AU - Hsu, Jee Ching
AU - See, Lai Chu
AU - Chai, Chok Yung
PY - 2007
Y1 - 2007
N2 - The effect of propofol on neuronal activity in the rostral ventrolateral medulla (RVLM) is not well established. Therefore, we performed extracellular recording on neurons of the RVLM to investigate neuronal activity before and after administration of intravenous propofol. The mean systemic arterial pressure (MSAP), heart rate and integrated neuronal firing rate (INFR) in the RVLM were continuously recorded in anesthetized cats before and after intravenous injection of 2 mg/kg propofol or supplemental injections of 1, 2 and 4 mg/kg propofol that were given respectively. Additionally, we compared the MSAP, heart rate (HR), and INFR in the RVLM following intravenous injection of 2 mg/kg propofol or 12.5 μg/kg nitroprusside. Neuronal firing was dose-dependently and reversibly inhibited after the supplemental doses of 1, 2 and 4 mg/kg propofol. The control INFR was 14.2 ± 9.9 Hz, and this decreased to 12.1 ± 9.4 Hz after the first dose of propofol (P = 0.085 vs. control), and further decreased to 9.3 ± 7.7 Hz (P = 0.001 vs. control) and 7.5 ± 7.7 Hz (P < 0.001 vs. control) after the second and third doses of propofol, respectively. Besides, SAP and HR were dose-dependently decreased by propofol as well. However, the effects of propofol and nitroprusside on neuronal activity in the RVLM differed. Propofol inhibited neuronal firing, whereas nitroprusside activated neuronal firing. In conclusion, propofol may dose-dependently inhibit spontaneous neuronal activity and the baroreflex in the RVLM.
AB - The effect of propofol on neuronal activity in the rostral ventrolateral medulla (RVLM) is not well established. Therefore, we performed extracellular recording on neurons of the RVLM to investigate neuronal activity before and after administration of intravenous propofol. The mean systemic arterial pressure (MSAP), heart rate and integrated neuronal firing rate (INFR) in the RVLM were continuously recorded in anesthetized cats before and after intravenous injection of 2 mg/kg propofol or supplemental injections of 1, 2 and 4 mg/kg propofol that were given respectively. Additionally, we compared the MSAP, heart rate (HR), and INFR in the RVLM following intravenous injection of 2 mg/kg propofol or 12.5 μg/kg nitroprusside. Neuronal firing was dose-dependently and reversibly inhibited after the supplemental doses of 1, 2 and 4 mg/kg propofol. The control INFR was 14.2 ± 9.9 Hz, and this decreased to 12.1 ± 9.4 Hz after the first dose of propofol (P = 0.085 vs. control), and further decreased to 9.3 ± 7.7 Hz (P = 0.001 vs. control) and 7.5 ± 7.7 Hz (P < 0.001 vs. control) after the second and third doses of propofol, respectively. Besides, SAP and HR were dose-dependently decreased by propofol as well. However, the effects of propofol and nitroprusside on neuronal activity in the RVLM differed. Propofol inhibited neuronal firing, whereas nitroprusside activated neuronal firing. In conclusion, propofol may dose-dependently inhibit spontaneous neuronal activity and the baroreflex in the RVLM.
KW - Bradycardia
KW - Extracellular recording
KW - Hypotension
KW - Propofol
KW - Rostral ventrolateral medulla
UR - http://www.scopus.com/inward/record.url?scp=46649111358&partnerID=8YFLogxK
M3 - 文章
C2 - 18274161
AN - SCOPUS:46649111358
SN - 0304-4920
VL - 50
SP - 251
EP - 257
JO - Chinese Journal of Physiology
JF - Chinese Journal of Physiology
IS - 5
ER -