Propofol effects on excitatory synaptic efficacy in the CA1 region of the developing hippocampus.
The anesthetic, propofol, effectively suppresses excitatory synaptic transmission and facilitates long-term depression (LTD) in the CA1 region of the hippocampus. Here, we have examined whether these effects are different in the developing hippocampus. We found that propofol in suppressing whole-cell excitatory postsynaptic currents (EPSC) was more effective in 21 day old rats than either in 7 day old rats or under the condition of high intracellular chloride concentration in 21 day old rats. Furthermore, the propofol concentration to facilitate the NMDA receptor-dependent LTD was lower at postnatal day 21 than at postnatal day 7. Interestingly, the decay time of EPSC was decreased during the development from postnatal day 7 to 21, but it was increased by the recording condition of high intracellular chloride concentration or by propofol administration. All these effects of propofol were dependent on the chloride channel opening. These observations suggest that propofol may induce differential anesthetic effects in the developing hippocampus, at least partially, depending on the intracellular chloride concentration.
Sun
Xuehua
X
Anaesthesiological Section, Union Hospital affiliated to TongJi Medical College, Huazhong University of Technology, Wuhan 430074, PR China.
Zhang
Jichuan
J
Li
Hongbin
H
Zhang
Zhi
Z
Yang
Jianli
J
Cui
Minghu
M
Zeng
Bangxiong
B
Xu
Tianle
T
Cao
Jun
J
Xu
Lin
L
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D002712:Chlorides / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004558:Electric Stimulation / Q000379:methods; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects*; D018756:GABA Antagonists / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects* / Q000254:growth & development*; D006993:Hypnotics and Sedatives / Q000494:pharmacology*; D066298:In Vitro Techniques; D036881:Long-Term Synaptic Depression / Q000187:drug effects; D018408:Patch-Clamp Techniques / Q000379:methods; D010852:Picrotoxin / Q000494:pharmacology; D015742:Propofol / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D009435:Synaptic Transmission / Q000187:drug effects*; D013997:Time Factors
D002712:Chlorides; D018756:GABA Antagonists; D006993:Hypnotics and Sedatives; D010852:Picrotoxin; D015742:Propofol