Paredes R G, Holmes G M, Sachs B D, Agmo A
Escuela de Psicología, Universidad Anáhuac, México D.F.
Behav Neural Biol. 1993 Sep;60(2):118-22. doi: 10.1016/0163-1047(93)90201-r.
The administration of GABA-transaminase inhibitors (GABA-TIs) to male rats reduces the proportion of mounts that result in intromissions. Copulatory pelvic thrusting remains normal, despite the fact that animals treated with GABA-TIs show gross deficiencies in other motor acts. In order to determine whether altered sexual behavior produced by GABA-TI could be due to deficiencies in activity of striated penile muscles, we recorded the electromyographic (EMG) activity of the ischiocavernosus (IC) muscle during copulation in male rats treated with sodium valproate. The duration of IC EMG bursts was reduced by sodium valproate in separate tests that allowed or prevented intromission. There was no effect on EMG amplitude or frequency. It is suggested that insufficient activity of the IC muscles reduces the likelihood of vaginal penetration. The actions of GABA may be localized to hypothalamic or brain stem nuclei with GABAergic projections to the spinal motoneurons controlling the IC muscles, or GABA may act directly on these neurons.
给雄性大鼠施用γ-氨基丁酸转氨酶抑制剂（GABA-TIs）会降低导致插入的爬跨比例。尽管用GABA-TIs处理的动物在其他运动行为上表现出明显缺陷，但交配时的骨盆推力仍保持正常。为了确定GABA-TI引起的性行为改变是否可能是由于横纹阴茎肌肉活动不足所致，我们记录了用丙戊酸钠处理的雄性大鼠交配期间坐骨海绵体肌（IC）的肌电图（EMG）活动。在允许或阻止插入的单独试验中，丙戊酸钠降低了IC肌电爆发的持续时间。对肌电幅度或频率没有影响。提示IC肌肉活动不足会降低阴道插入的可能性。GABA的作用可能定位于具有向控制IC肌肉的脊髓运动神经元投射的γ-氨基丁酸能投射的下丘脑或脑干核，或者GABA可能直接作用于这些神经元。
