The aim of this study was to examine whether thioxanthine-type antipsychotics (chlorprothixene and cis(z)-flupenthixol) and phenothiazine-type antipsychotics (chlorpromazine and fluphenazine) produced spinal anesthesia. Using a rat model of intrathecal injection, we evaluated spinal anesthesia of antipsychotic drugs (chlorprothixene, cis(z)-flupenthixol, chlorpromazine, and fluphenazine) and bupivacaine, a known local anesthetic. At a same dose of 2.31 mu mol/kg, chlorprothixene had the most potent spinal blockades (P < 0.001) and the longest duration of action (P < 0.001) of motor function and nociception among those antipsychotic drugs. On the 50% effective dose (ED50) basis, the ranks of potencies were chlorprothixene=bupivacaine > cis(z)- flupenthixol > chlorpromazine > fluphenazine (P < 0.01 for the differences) in dose-response studies. At an equianesthetic basis (ED25, ED50, and ED75), the spinal block duration caused by chlorprothixene, cis(z)-flupenthixol, chlorpromazine or fluphenazine was longer than that caused by bupivacaine (P < 0.05). These results showed that chlorprothixene produced a similar potency and longer duration of spinal anesthesia than did bupivacaine, whereas several other antipsychotics produced less potency than did bupivacaine. (c) 2012 Elsevier B.V. All ights reserved.
關聯:
European Journal of Pharmacology v.693 n.1-3 pp.31-36
