Georgia State University, Neuroscience Institute, 100 Piedmont Avenue NE, Atlanta, GA 30303, USA.
Physiol Behav. 2012 Feb 28;105(4):1021-7. doi: 10.1016/j.physbeh.2011.11.007. Epub 2011 Dec 2.
Vaginal marking is a stereotyped scent marking behavior in female Syrian hamsters used to attract male hamsters for mating. Although the modulation of vaginal marking by hormones and odors is well understood, the motor control of this proceptive reproductive behavior remains unknown. Therefore, we used X-ray videography to visualize individual bone movements during vaginal marking. Kinematic analyses revealed several consistent motor patterns of vaginal marking. Despite exhibiting a diversity of trial-to-trial non-marking behaviors (e.g. locomotor stepping), we found that lowering and raising the pelvis consistently corresponded with coordinated flexion and extension cycles of the hip, knee, and tail, suggesting that these movements are fundamental to vaginal marking behavior. Surprisingly, we observed only small changes in the angles of the pelvic and sacral regions, suggesting previous reports of pelvic rotation during vaginal marking may need to be reconsidered. From these kinematic data, we inferred that vaginal marking is primarily due to the actions of hip and knee extensor muscles of the trailing leg working against gravity to support the weight of the animal as it controls the descent of the pelvis to the ground. The cutaneous trunci muscle likely mediates the characteristic flexion of the tail. Interestingly, this tail movement occurred on the same time scale as the joint kinematics suggesting possible synergistic recruitment of these muscle groups. These data therefore provide new targets for future studies examining the peripheral control of female reproductive behaviors.
阴道标记是雌性叙利亚仓鼠用于吸引雄性仓鼠进行交配的一种刻板的气味标记行为。尽管激素和气味对阴道标记的调节作用已得到充分理解，但这种亲代生殖行为的运动控制仍不清楚。因此，我们使用 X 射线录像来可视化阴道标记过程中的个体骨骼运动。运动学分析揭示了阴道标记的几种一致的运动模式。尽管表现出多种试验间的非标记行为（例如，运动性踏步），但我们发现骨盆的降低和升高与髋、膝和尾的协调屈伸循环一致，这表明这些运动是阴道标记行为的基础。令人惊讶的是，我们仅观察到骨盆和荐骨区域角度的微小变化，这表明先前关于阴道标记过程中骨盆旋转的报告可能需要重新考虑。从这些运动学数据中，我们推断阴道标记主要是由于后肢的髋关节和膝关节伸肌的作用，这些肌肉对抗重力以支撑动物的重量，同时控制骨盆下降到地面。腹外斜肌可能介导了尾巴的特征性弯曲。有趣的是，这种尾巴运动与关节运动学发生在同一时间尺度上，这表明这些肌肉群可能存在协同募集。因此，这些数据为未来研究雌性生殖行为的外周控制提供了新的目标。
