caa a22 4500 445374179 CHVBK 20180317142957.0 cr unu---uuuuu 170323e20111001xx s 000 0 eng 10.1007/s00540-011-1186-4 doi (NATIONALLICENCE)springer-10.1007/s00540-011-1186-4 Effects of propofol and pentobarbital on calcium concentration in presynaptic boutons on a rat hippocampal neuron [Elektronische Daten] [Shinichi Ito, Hitomi Sugiyama, Seiko Kitahara, Yoshimi Ikemoto, Takeshi Yokoyama] Purpose: Numerous reports suggest that intravenously administered (IV) anesthetics affect postsynaptic events in the central nervous system. However, there is little evidence about how general anesthetics influence the presynaptic processes. The level of presynaptic calcium (Ca2+) concentration ([Ca2+]pre) regulates neurotransmitter release. In this study, we investigated the effects of anesthetic propofol IV and the barbiturate pentobarbital on neurotransmitter release by measuring [Ca2+]pre in the presynaptic nerve terminals (boutons) on a dissociated single hippocampal rat neuron. Methods: Sprague-Dawley rats 10-14days old were decapitated under pentobarbital anesthesia, and brain slices were prepared. The hippocampal CA1 area was touched with a fire-polished glass pipette, which vibrated horizontally, and neurons were dissociated, along with the attached presynaptic boutons. The presynaptic boutons were visualized under a confocal laser-scanning microscope after staining with FM1-43 dye, and [Ca2+]pre was measured with acetoxymethyl ester of fluo-3 (fluo-3 AM). Results: High potassium (K+) (15-90mM) increased the [Ca2+]pre in the Ca2+-containing solution in a concentration-dependent manner. Whereas propofol (10μM) and pentobarbital (300μM) suppressed the high K+ (60mM)-induced increase in [Ca2+]pre in the boutons attached to the dendrite, they did not affect [Ca2+]pre in the boutons attached to the soma or dendrite base. As a large majority of excitatory synapses are located on dendritic spines, these agents may affect Ca2+ mobilization in the excitatory presynaptic boutons. Conclusions: Propofol and pentobarbital may affect neurotransmitter release from the excitatory presynaptic nerve terminals due to inhibition of increase in [Ca2+]pre. Japanese Society of Anesthesiologists, 2011 Propofol nationallicence Pentobarbital nationallicence Calcium signaling nationallicence Presynaptic terminals nationallicence Hippocampus nationallicence Ito Shinichi Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, 812-8582, Fukuoka, Japan aut Sugiyama Hitomi Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, 812-8582, Fukuoka, Japan aut Kitahara Seiko Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, 812-8582, Fukuoka, Japan aut Ikemoto Yoshimi Hisatsune Hospital, Fukuoka, Japan aut Yokoyama Takeshi Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, 812-8582, Fukuoka, Japan aut Journal of Anesthesia Springer Japan 25/5(2011-10-01), 727-733 0913-8668 25:5<727 2011 25 540 https://doi.org/10.1007/s00540-011-1186-4 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00540-011-1186-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Ito Shinichi Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, 812-8582, Fukuoka, Japan aut NATIONALLICENCE 700 1- Sugiyama Hitomi Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, 812-8582, Fukuoka, Japan aut NATIONALLICENCE 700 1- Kitahara Seiko Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, 812-8582, Fukuoka, Japan aut NATIONALLICENCE 700 1- Ikemoto Yoshimi Hisatsune Hospital, Fukuoka, Japan aut NATIONALLICENCE 700 1- Yokoyama Takeshi Department of Dental Anesthesiology, Faculty of Dental Science, Kyushu University, 812-8582, Fukuoka, Japan aut NATIONALLICENCE 773 0- Journal of Anesthesia Springer Japan 25/5(2011-10-01), 727-733 0913-8668 25:5<727 2011 25 540 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer