Hoffman N W, Gerall A A, Kalivas P W
Department of Psychology, Tulane University, New Orleans, LA 70118.
Physiol Behav. 1987;41(6):563-9. doi: 10.1016/0031-9384(87)90312-x.
Serotonin (5-HT), 5-hydroxyindolacetic acid (5-HIAA), dopamine (DA), dihydroxyphenylacetic acid (DOPAC), and norepinephrine (NE) concentrations in seven brain regions were compared in sexually refractory, physically active, and inactive male rats. Also examined were 5-HIAA/5-HT and DOPAC/DA concentration ratios. Sexually refractory males were permitted uninterrupted copulation with successive receptive females until they failed to mount or ejaculate in a set period. Physically active males ran in motor-driven activity wheels except during the postejaculatory refractory periods of experimental animals, and inactive males remained alone in testing arenas. Significant group differences were found only in monoamine concentrations in the medial preoptic area (MPOA) and the medial forebrain bundle (MFB). In the MPOA, 5-HT concentration was elevated in sexually refractory males, as was DA in both refractory and active animals. In the MFB, 5-HT concentration was increased in active males. MFB DOPAC levels of sexually refractory rats significantly correlated inversely with their ejaculation totals, as did MFB and dorsal raphe (DR) NE levels. The results suggest that the MPOA is a forebrain target for inhibitory influences on male rat sexual behavior of ascending serotonergic fibers and that increased MFB 5-HT and MPOA DA may be associated with general activity.
对性不应期、身体活跃和不活跃的雄性大鼠七个脑区中的血清素（5-羟色胺，5-HT）、5-羟吲哚乙酸（5-HIAA）、多巴胺（DA）、二羟基苯乙酸（DOPAC）和去甲肾上腺素（NE）浓度进行了比较。还检测了5-HIAA/5-HT和DOPAC/DA浓度比。性不应期的雄性大鼠与相继处于接受状态的雌性大鼠进行不间断交配，直到它们在规定时间内无法爬上或射精。身体活跃的雄性大鼠在电动活动轮中跑动，但实验动物射精后的不应期除外，不活跃的雄性大鼠则单独留在测试场地。仅在内侧视前区（MPOA）和内侧前脑束（MFB）的单胺浓度中发现了显著的组间差异。在MPOA中，性不应期雄性大鼠的5-HT浓度升高，不应期和活跃动物的DA浓度均升高。在MFB中，活跃雄性大鼠的5-HT浓度增加。性不应期大鼠的MFB DOPAC水平与其射精总数呈显著负相关，MFB和中缝背核（DR）的NE水平也是如此。结果表明，MPOA是前脑的一个靶点，对雄性大鼠性行为有抑制作用的上行5-羟色胺能纤维会对其产生影响，且MFB中5-HT和MPOA中DA的增加可能与一般活动有关。
