Propofol inhibited the delayed rectifier potassium current (I(k)) via activation of protein kinase C epsilon in rat parietal cortical neurons.
Propofol has been shown to exert neuroprotective effects. Delayed rectifier potassium current (I(K)) was reported to be closely related to neuronal damage. This study was designed to test the effects of propofol on I(K) in rat parietal cortical neurons and the involvement of PKC in this activity. Whole-cell patch-clamp recordings were performed in rat parietal cortical neurons. The amplitudes of I(K) were recorded before and after the addition of different concentrations of propofol. Propofol concentration-dependently inhibited I(K) with an IC50 value of 36.3±2.7 μM. Moreover, propofol caused a downward shift of the I-V curve of I(K) in a concentration dependent manner. The kinetics of I(K) was altered by propofol, with decreased activation and delayed recovery of I(K). Pretreatment with calphostin-C (a non-selective inhibitor of PKC) or PKC epsilon translocation inhibitor peptide (PKC epsilon inhibitor) abrogated the inhibition of I(K) by propofol. In conclusion, propofol inhibited I(K) via the activation of PKC epsilon in rat cerebral parietal cortical neurons.
Department of Anesthesiology, The Second Affiliated Hospital of Harbin Medical University, Harbin, China.
Chun-Yu
CY
Song
Hong-Jie
HJ
Xi
Lei
L
Yang
Li-Hui
LH
Qu
Zi-Yong
ZY
Yue
Jin
J
Zhou
Xiao-Guang
XG
Cui
Wei
W
Gao
Nan
N
Wang
Zhen-Wei
ZW
Pan
Wen-Zhi
WZ
Li
D000818:Animals; D051668:Delayed Rectifier Potassium Channels / Q000037:antagonists & inhibitors*; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D009281:Naphthalenes / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000494:pharmacology*; D010296:Parietal Lobe / Q000187:drug effects / Q000378:metabolism; D018408:Patch-Clamp Techniques; D015742:Propofol / Q000008:administration & dosage / Q000494:pharmacology*; D051744:Protein Kinase C-epsilon / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D051668:Delayed Rectifier Potassium Channels; D009281:Naphthalenes; D018696:Neuroprotective Agents; D051744:Protein Kinase C-epsilon; C058819:calphostin C; D015742:Propofol