Ballal P M, Mandhane S N, Chopde C T, Muthal A V
Department of Pharmaceutical Sciences, Nagpur University Campus, Nagpur.
Indian J Physiol Pharmacol. 1996 Jan;40(1):95-7.
The influence of GABA agonists and antagonists on analgesic activity of imipramine (IMA, 20 mg/kg, ip) was studied using the hotplate method. Administration of GABAA receptor agonist muscimol (1 mg/kg, ip), GABAB receptor agonist baclofen (3 mg/kg, ip) or GABA-T inhibitor aminooxyacetic acid (25 mg/kg, ip) increased the analgesic effect of IMA. On the other hand pretreatment of GABAA receptor antagonist bicucukline (2 mg/kg ip), GABAB receptor antagonist delta-amino-n-valeric acid (50 mg/kg, ip) or GABA synthesis inhibitor thiosemicarbazide (50 mg/kg, ip) attenuated the IMA analgesia. These results suggest that the analgesic action of IMA may be mediated by functional alteration of a central GABAergic mechanism and/or subsequent stimulation of GABA receptors.
采用热板法研究了γ-氨基丁酸（GABA）激动剂和拮抗剂对丙咪嗪（IMA，20mg/kg，腹腔注射）镇痛活性的影响。给予GABAA受体激动剂蝇蕈醇（1mg/kg，腹腔注射）、GABAB受体激动剂巴氯芬（3mg/kg，腹腔注射）或GABA转氨酶抑制剂氨氧乙酸（25mg/kg，腹腔注射）可增强IMA的镇痛效果。另一方面，预先给予GABAA受体拮抗剂荷包牡丹碱（2mg/kg，腹腔注射）、GABAB受体拮抗剂δ-氨基-n-戊酸（50mg/kg，腹腔注射）或GABA合成抑制剂氨基硫脲（50mg/kg，腹腔注射）可减弱IMA的镇痛作用。这些结果表明，IMA的镇痛作用可能是由中枢GABA能机制的功能改变和/或随后对GABA受体的刺激介导的。
