TY - JOUR
T1 - Etomidate depresses lumbar dorsal horn neuronal responses to noxious thermal stimulation in rats
AU - Mitsuyo, Toshihiko
AU - Antognini, Joseph F.
AU - Carstens, Earl
PY - 2006/4
Y1 - 2006/4
N2 - Etomidate is a widely used IV anesthetic, but little is known about its analgesic properties, in particular, its effects on spinal cord neuronal responses to noxious stimuli. We hypothesized that etomidate would depress lumbar neuronal responses to noxious heat. Rats (n = 15) were anesthetized with isoflurane (1.2%) and laminectomy was performed to record single unit activity. Lumbar neuronal responses to noxious thermal (52°C, 12 s) stimulation of the hindpaw were recorded before and every 2 min (up to 13 min postinjection) after administration of etomidate. The responses at peak effect of etomidate (as a percentage of the control response) were 63% ± 16%, 63% ± 16%, 38% ± 25%, 36% ± 30%, and 41% ± 26% for the 0.125, 0.25, 0.5,1 and 2 mg/kg doses, respectively. The responses quickly recovered, usually by the 10-min period postinjection. Similar responses were obtained in decerebrate, isoflurane-free rats administered etomidate and in isoflurane-anesthetized rats administered propofol. These data demonstrate that etomidate depresses spinal cord neuronal responses to noxious stimulation and is a possible mechanism by which this drug might produce analgesia.
AB - Etomidate is a widely used IV anesthetic, but little is known about its analgesic properties, in particular, its effects on spinal cord neuronal responses to noxious stimuli. We hypothesized that etomidate would depress lumbar neuronal responses to noxious heat. Rats (n = 15) were anesthetized with isoflurane (1.2%) and laminectomy was performed to record single unit activity. Lumbar neuronal responses to noxious thermal (52°C, 12 s) stimulation of the hindpaw were recorded before and every 2 min (up to 13 min postinjection) after administration of etomidate. The responses at peak effect of etomidate (as a percentage of the control response) were 63% ± 16%, 63% ± 16%, 38% ± 25%, 36% ± 30%, and 41% ± 26% for the 0.125, 0.25, 0.5,1 and 2 mg/kg doses, respectively. The responses quickly recovered, usually by the 10-min period postinjection. Similar responses were obtained in decerebrate, isoflurane-free rats administered etomidate and in isoflurane-anesthetized rats administered propofol. These data demonstrate that etomidate depresses spinal cord neuronal responses to noxious stimulation and is a possible mechanism by which this drug might produce analgesia.
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U2 - 10.1213/01.ane.0000204764.13637.d4
DO - 10.1213/01.ane.0000204764.13637.d4
M3 - Article
C2 - 16551918
AN - SCOPUS:33645508988
VL - 102
SP - 1169
EP - 1173
JO - Anesthesia and Analgesia
JF - Anesthesia and Analgesia
SN - 0003-2999
IS - 4
ER -