ラット Propofol 投与後に三叉神経脊髄路核および上部頸髄に発現するpERK陽性細胞の動態 Expression of pERK-LI cells in the trigeminal spinal nucleus caudalis following propofol administration in rats
Propofol (PRO) is frequently used as the reliable sedative agent in clinic situation because it is safe and easy to control the depth of sedative level. PRO, however, has weak analgesic action even causing acute pain sensation during intravenous infusion. For the clinical use of sedatives, the invasive action such as pain should be relieved. It is very important to know underlying mechanisms of the weak analgesic action of propofol in order to improve clinical use of PRO.<br> We studied the phosphorylated Extracellular Signal-regulated Kinase (pERK) expression in the trigeminal spinal nucleus and upper cervical nociceptive neurons to clarify the central mechanism of the enhancement of trigeminal transmission.<br> We observed that a large number of pERK-LI cells were expressed in Vi/Vc zone, middle Vc and Vc-C2 zone immediately after the large amount of propofol injection. The number of pERK-LI cells was increased following increase in the amount of PRO administration. We also observed that the expression of pERK-LI cells was depressed after the lidocaine injection before PRO injection.<br> The present findings suggest that PRO has a strong ability to enhance nociceptive neuronal activity in the trigeminal region through the primary afferent nociceptors innervated in the cervical vein, resulting in the central sensitization of the trigeminal nociceptive pathways during infusion.
- Pain research : the journal of the Japanese Society for the Study of Pain = 日本疼痛学会誌
Pain research : the journal of the Japanese Society for the Study of Pain = 日本疼痛学会誌 22(1), 19-25, 2007-02-26