Is neurotransmitter release involved in the mechanism of general anesthesia?

  • Kazuyoshi HirotaEmail author
  • Tetsuya Kushikata
  • Daiki Takekawa
  • Mihoko Kudo
Short Communication



It is believed that neurotransmitters release modulates general anesthesia via several receptors system which are molecular targets for anesthetic agents in young-adult rats. However, middle-aged rats have rarely been used. Therefore, we studied in this age group.

Materials and Methods

After approval of our protocol by the institutional committee on animal research, 116 middle aged Sprague–Dawley rats were assigned to ketamine (K: n = 74) and propofol (P: n = 42) anesthesia groups. Rats were decapitated 0, 20 60 and 120 min after ip K (100 mg/kg) or P (80 mg/kg), respectively. Melanin-concentrating hormone (MCH), orexin A (OXA) and noradrenaline contents in the pons, hypothalamus, hippocampus and cerebrocortex were measured by a commercial enzyme-linked immunosorbent assay (ELISA) or high-performance liquid chromatography.


Neurotransmitter content in all brain regions did not significantly change following K or P administration.


Therefore, we question whether neurotransmitter release contributes to general anesthesia.


Neurotransmitter release Aging Rats Mechanism of general anesthesia 



We thank Professor David G Lambert (University Department of Cardiovascular Sciences, Anaesthesia, Critical Care and Pain Management, Leicester Royal infirmary, Leicester, UK) for his valuable comments.


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Copyright information

© Japanese Society of Anesthesiologists 2019

Authors and Affiliations

  1. 1.Department of AnesthesiologyHirosaki University Graduate School of MedicineHirosakiJapan

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