Sachs B D, Akasofu K, Citron J H, Daniels S B, Natoli J H
Department of Psychology, University of Connecticut, Storrs 06269-1020.
Physiol Behav. 1994 Jun;55(6):1073-9. doi: 10.1016/0031-9384(94)90390-5.
Five experiments demonstrated that noncontact stimulation from estrous females evokes penile erection in a high proportion of sexually experienced male rats. In Experiment 1, 23 of 24 males (96%) displayed erections while separated from estrous females by a wire-mesh barrier, compared with 8% when no female was present. In Experiment 2, inaccessible estrous females stimulated erection in 100% of males, whereas only 38% responded to inaccessible unfamiliar males and 0% to inaccessible preferred food or an empty cage (n = 8/group). These data suggest that nonsexual arousing stimuli do not readily evoke erections. Experiments 3 and 4 demonstrated that bedding collected from estrous females is highly attractive to males, but is ineffective in promoting erections even when the males can burrow in the bedding. Therefore, estrous odors alone are apparently insufficient to stimulate erection. In Experiment 5, the percentage of males (n = 18) responding with erection did not vary significantly as a function of their exposure to ovariectomized females (67%), receptive but nonproceptive females (83%), or proceptive females (89%), but these stimuli were progressively more effective in reducing erection latency and increasing the number of erections displayed, suggesting that behavioral cues emitted by females promote erection. The display of erection by rats under the conditions used in these studies satisfies conventional criteria for recognition as psychogenic erections, which we have provisionally defined as erections that occur without concurrent somesthetic stimulation. The availability of a rodent model of psychogenic erection should foster analysis of its physiological mediation.
五项实验表明，处于发情期的雌性大鼠的非接触性刺激能使高比例有性经验的雄性大鼠阴茎勃起。在实验1中，24只雄性大鼠中有23只（96%）在通过铁丝网屏障与发情期雌性大鼠隔开时出现勃起，而没有雌性大鼠在场时这一比例为8%。在实验2中，无法接触到的发情期雌性大鼠使100%的雄性大鼠勃起，而只有38%的雄性大鼠对无法接触到的陌生雄性大鼠有反应，对无法接触到的喜爱食物或空笼子有反应的比例为0%（每组n = 8）。这些数据表明，非性唤起刺激不容易引发勃起。实验3和实验4表明，从发情期雌性大鼠收集的垫料对雄性大鼠极具吸引力，但即使雄性大鼠能在垫料中打洞，也无法有效促进勃起。因此，仅发情期气味显然不足以刺激勃起。在实验5中，有勃起反应的雄性大鼠（n = 18）的比例，在接触卵巢切除的雌性大鼠（67%）、可接受但未处于发情前期的雌性大鼠（83%）或处于发情前期的雌性大鼠（89%）时，并未随接触情况而有显著变化，但这些刺激在缩短勃起潜伏期和增加勃起次数方面逐渐更有效，这表明雌性大鼠发出的行为线索能促进勃起。在这些研究中所使用条件下大鼠出现的勃起，符合被认定为心因性勃起的传统标准，我们暂时将心因性勃起定义为在没有同时存在的躯体感觉刺激情况下发生的勃起。心因性勃起啮齿动物模型的可得性应有助于对其生理调节进行分析。
