• Brain research · Mar 2005

    Comparative Study

    The interaction of noradrenaline with sevoflurane on GABA(A) receptor-mediated inhibitory postsynaptic currents in the rat hippocampus.

    • Koichi Nishikawa, Kazuhiro Kubo, Junko Ishizeki, Tomonori Takazawa, Shigeru Saito, and Fumio Goto.
    • Department of Anesthesiology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi City 371-8511, Japan. nishikaw@med.gunma-u.ac.jp
    • Brain Res. 2005 Mar 28;1039(1-2):153-61.

    AbstractLittle is known about the interaction of noradrenaline with volatile anesthetics in inhibitory synaptic transmission. The purpose of the present study was to investigate the interactions of noradrenaline and sevoflurane on inhibitory synaptic transmission mediated by GABA(A) receptors in the rat hippocampus. Pharmacologically isolated GABA(A) receptor-mediated IPSCs were recorded with whole-cell patch-clamp techniques in pyramidal neurons of the CA1 region of rat hippocampal slices. The actions of noradrenaline, noradrenaline analog, sevoflurane, and the interactions of these agents on the frequency and kinetics of spontaneous GABA(A) receptor-mediated IPSCs were studied. Noradrenaline (10 microM) caused an increase in the frequency of action potential-dependent sIPSCs. These effects were completely reversed by the addition of tetrodotoxin (1 microM), suggesting that noradrenaline produces the discharge of GABAergic interneurons innervating on pyramidal cells via adrenoceptors. Although sevoflurane (0.40 mM, 20 min) slightly depressed the amplitude of sIPSCs, sevoflurane significantly prolonged the decay time constant to 451.1 +/- 89.0% of control (n = 9, P < 0.001) without affecting the rise time. In addition, sevoflurane increased the frequency of sIPSCs up to 3-fold. However, pretreatment of cadmium, multiple Ca channel blocker, abolished sevoflurane effects on the frequency whereas the effects on the decay were still observed. Application of both noradrenaline and sevoflurane produced a significant increase of the IPSC frequency than that of noradrenaline alone or sevoflurane alone with prolonged decays. These results provide evidence that both agents have additive effects on GABAergic synaptic transmission at the central nervous system via different mechanisms.

      Pubmed     Full text   Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…