Librizzi Laura, Pastori Chiara, de Grazia Ugo, Croci Danilo, de Curtis Marco
Department of Experimental Neurophysiology, Istituto Nazionale Neurologico Carlo Besta, via Celoria 11, 20133 Milano, Italy.
Neurosci Lett. 2005;380(1-2):66-9. doi: 10.1016/j.neulet.2005.01.002. Epub 2005 Jan 25.
Electrophysiological and metabolic activities in brain tissue preparations maintained in vitro may be influenced by the persistent effect of anesthetic drugs utilized during tissue dissection. In order to clarify this issue, we studied elimination kinetics of the barbiturate thiopental from the brain parenchyma in the isolated guinea pig brain maintained in vitro, arterially perfused with a protein-free saline solution [M. de Curtis, G. Biella, C. Buccellati, G. Folco, Simultaneous investigation of the neuronal and vascular compartments in the guinea pig brain isolated in vitro, Brain Res. Protoc. 3 (1998) 21-28]. At the onset of anesthesia induced by a single i.p. injection of 125 mg/kg thiopental, the brain concentration of the drug, measured by high-performance liquid chromatographic assay, was 44.22+/-5.1 mg/L (mean+/-S.E.; n=7). After 30 min of arterial perfusion in vitro with a thiopental-free solution, the cerebral levels of the barbiturate decreased to 2.03+/-0.56 mg/L (n=3), and reached values close to zero within 1 h. No significant changes in thiopental elimination curve were observed when in vitro perfusion rate was either increased or decreased. The study demonstrates that thiopental is rapidly eliminated from the brain tissue with a mono-exponential kinetic. It can be concluded that barbiturate anesthesia utilized during brain dissection is not likely to influence activities recorded from the in vitro isolated brain preparation.
在体外维持的脑组织制剂中的电生理和代谢活动可能会受到组织解剖过程中使用的麻醉药物的持续影响。为了阐明这个问题，我们研究了在体外维持的分离豚鼠脑中，用无蛋白盐溶液进行动脉灌注时，巴比妥类药物硫喷妥钠从脑实质中的消除动力学[M. de Curtis, G. Biella, C. Buccellati, G. Folco, 体外分离豚鼠脑神经元和血管区室的同步研究，《脑研究实验手册》3 (1998) 21 - 28]。通过单次腹腔注射125 mg/kg硫喷妥钠诱导麻醉开始时，用高效液相色谱法测定的药物脑浓度为44.22±5.1 mg/L（平均值±标准误；n = 7）。在用无硫喷妥钠溶液进行体外动脉灌注30分钟后，巴比妥类药物的脑水平降至2.03±0.56 mg/L（n = 3），并在1小时内降至接近零的值。当体外灌注速率增加或降低时，硫喷妥钠消除曲线未观察到显著变化。该研究表明硫喷妥钠以单指数动力学从脑组织中快速消除。可以得出结论，在脑解剖过程中使用的巴比妥类麻醉不太可能影响从体外分离的脑制剂记录的活动。
