Hernandez-Gonzalez M, Guevara M A, Morali G, Cervantes M
Instituto de Neurociencias, Universidad de Guadalajara, Jalisco, México.
Physiol Behav. 1997 Feb;61(2):285-91. doi: 10.1016/s0031-9384(96)00367-8.
Multiple unit activity (MUA) was recorded from the ventral tegmental area (VTA) and mesencephalic locomotor region (MLR) during copulatory behavior of freely moving male rats. Simultaneous accelerometric recordings of the copulatory pelvic thrusting performed by the male rat were taken to precisely correlate in time the changes in MUA with well defined elements of copulation. The baseline MUA firing rates recorded in the quiet-alert condition in the VTA and in the MLR were significantly increased during pursuit of the female by the male; significantly higher MUA firing rates were found in the VTA at the 500 ms periods before and during the execution of pelvic thrusting in mount, intromission, and ejaculation responses as compared to the baseline, and returned to this value when these responses ended. The maximum MUA firing rate in the MLR was obtained during the execution of pelvic thrusting in each copulatory response, and it remained significantly elevated, as compared to the baseline, after thrusting and at the postintromission and postejaculatory genital grooming, then decreasing to basal values at the initial part of the postejaculatory interval. The fact that the highest changes in MUA were related to pelvic thrusting suggests a major participation of both structures in the execution of motor copulatory responses.
在自由活动的雄性大鼠交配行为期间，记录了腹侧被盖区（VTA）和中脑运动区（MLR）的多单位活动（MUA）。同时对雄性大鼠交配时骨盆推进行加速计记录，以便在时间上精确关联MUA的变化与明确的交配要素。在雄性追逐雌性期间，VTA和MLR在安静警觉状态下记录的基线MUA放电率显著增加；与基线相比，在骑跨、插入和射精反应中骨盆推进执行前500毫秒期间及执行期间，VTA中的MUA放电率显著更高，并且当这些反应结束时恢复到该值。在每次交配反应中骨盆推进执行期间获得MLR中的最大MUA放电率，与基线相比，在推进后以及插入后和射精后生殖器梳理时，该放电率仍显著升高，然后在射精后间隔初期降至基础值。MUA的最高变化与骨盆推进相关这一事实表明这两个结构在交配运动反应的执行中起主要作用。
