Orviz P, Cecchini B G, Andrés-Trelles F
Rev Esp Fisiol. 1986 Sep;42(3):309-13.
Electric stimulation of the rat forepaw evokes a negative potential (N-wave) at the ipsilateral cuneate nucleus. The responses of the N-wave to microiontophoretically applied GABA agonists and antagonists have been studied. Applications of GABA-A agonists (3-amino-propanesulfonic acid and muscimol) reduce the amplitude of the N-wave. This effect decreases during prolonged application, suggesting a desensitization of GABA-A receptors. In addition the effect of muscimol is reduced by (-)-bicuculline methiodide. Baclofen (a GABA-B agonist) also depresses the N-wave but its action lasts longer, is less reversible, shows no desensitization and is not blocked by (-)-bicuculline methiodide. The different responses of the N-wave to GABA-A and GABA-B agonists are compatible with the existence of different types of functional receptors for them in the cuneate nucleus of the rat. The receptors activated by muscimol (GABA-A) are clearly not the same as the ones activated by baclofen (conceivably GABA-B).
对大鼠前爪进行电刺激会在同侧楔束核诱发一个负电位（N波）。已经研究了N波对微量离子电泳施加的GABA激动剂和拮抗剂的反应。应用GABA-A激动剂（3-氨基丙烷磺酸和蝇蕈醇）会降低N波的幅度。在长时间应用期间这种效应会减弱，提示GABA-A受体脱敏。此外，(-)-荷包牡丹碱甲碘化物会减弱蝇蕈醇的效应。巴氯芬（一种GABA-B激动剂）也会抑制N波，但它的作用持续时间更长，可逆性较小，未显示脱敏且不被(-)-荷包牡丹碱甲碘化物阻断。N波对GABA-A和GABA-B激动剂的不同反应与大鼠楔束核中存在不同类型的功能性受体相一致。被蝇蕈醇激活的受体（GABA-A）显然与被巴氯芬激活的受体（可能是GABA-B）不同。
