Benedict G S, Williams C L
Columbia University, New York, New York 10027.
Horm Behav. 1993 Dec;27(4):449-69. doi: 10.1006/hbeh.1993.1033.
The purpose of these experiments is to compare the regional specificity (Experiment 1) and the hormonal modulation (Experiment 2) of the cutaneous initiation of lordosis in 4- to 6-day-old male and female rats (infants) and in 60- to 90-day-old female rats (adults). In Experiment 1, subjects were primed with 100 micrograms estradiol benzoate (EB) and 0.5 mg progesterone (P) and were denervated on the Waist (dermatomes L1-L3), Midriff (dermatomes T10-L3), Flanks (dermatomes L4-L6), or Sides (dermatomes T10-L6). In infants, there were no significant differences between males and females. Denervation of the Waist, Midriff, or Sides but not of the Flanks significantly decreased the percentage of subjects displaying lordosis, lordosis quotient (LQ), and mean lordosis duration; no significant differences were obtained among Waist-, Midriff, or Sides-denervated infants. In contrast, denervation of the Sides but not of the Waist significantly decreased LQ and mean lordosis intensity among adults. In Experiment 2, Waist-denervated infants and their surgical Controls were treated either with 100 micrograms EB and 0.5 mg P or with the oil vehicle; Waist-denervated adults and their surgical Controls received either 100 or 10 micrograms EB (no P). Regardless of hormone treatment, denervation of the Waist significantly decreased LQ and lordosis duration in infants and decreased LQ and lordosis intensity in adults. In infants, the only effect of priming with EB and P was to increase the percentage of pups showing lordosis and lordosis duration among the surgical Controls. In contrast, priming with 100 micrograms EB significantly increased the percentage of rats displaying lordosis, LQ, and lordosis intensity among Waist-denervated adults. These data suggest that cutaneous input from the Waist is important for eliciting lordosis in both infant and adult rats, and that the importance of this input is modulated by hormone priming in adult but not infant rats.
这些实验的目的是比较4至6日龄雄性和雌性大鼠（幼崽）以及60至90日龄雌性大鼠（成年大鼠）中，脊柱前凸皮肤起始的区域特异性（实验1）和激素调节（实验2）。在实验1中，给实验对象注射100微克苯甲酸雌二醇（EB）和0.5毫克孕酮（P）进行预处理，然后对其腰部（皮节L1-L3）、腹部（皮节T10-L3）、胁腹（皮节L4-L6）或体侧（皮节T10-L6）进行去神经支配。在幼崽中，雄性和雌性之间没有显著差异。腰部、腹部或体侧去神经支配，但胁腹去神经支配不显著降低表现出脊柱前凸的实验对象百分比、脊柱前凸商数（LQ）和平均脊柱前凸持续时间；腰部、腹部或体侧去神经支配的幼崽之间未获得显著差异。相比之下，体侧去神经支配而非腰部去神经支配显著降低成年大鼠的LQ和平均脊柱前凸强度。在实验2中，腰部去神经支配的幼崽及其手术对照组，要么用100微克EB和0.5毫克P处理，要么用油载体处理；腰部去神经支配的成年大鼠及其手术对照组接受100或10微克EB（无P）。无论激素处理如何，腰部去神经支配显著降低幼崽的LQ和脊柱前凸持续时间，以及成年大鼠的LQ和脊柱前凸强度。在幼崽中，用EB和P预处理的唯一效果是增加手术对照组中表现出脊柱前凸的幼崽百分比和脊柱前凸持续时间。相比之下，用100微克EB预处理显著增加腰部去神经支配成年大鼠中表现出脊柱前凸的大鼠百分比、LQ和脊柱前凸强度。这些数据表明，来自腰部的皮肤输入对于引发幼崽和成年大鼠的脊柱前凸都很重要，并且这种输入的重要性在成年大鼠中受激素预处理调节，而在幼崽中不受调节。
