Estrous changes in vaginal nociception in a rat model of endometriosis
Estrous changes in vaginal nociception in a rat model of endometriosis
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DOI：
10.1016/s0018-506x(03)00121-1
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发表时间：
2003-08-01
影响因子：
3.5
通讯作者：
Berkley, KJ
中科院分区：
文献类型：
--
作者：
Cason, AM;Samuelsen, CL;Berkley, KJ
子宫内膜异位症的大鼠模型中，子宫角(与对照组的脂肪相比)被自体移植到腹部，在那里它们形成囊肿，降低生育力，并产生阴道痛觉过敏。手术后2个月内，囊肿逐渐增大，然后进入平台期。随着雌激素水平的降低，囊肿会消退，当它们上升时会再次出现。基于阴道痛敏依赖于包囊的假设，本研究检验了两个预测：(1)术后痛觉过敏将与包囊平行发展，(2)痛觉过敏将随发情而变化，当雌激素水平较高时(发情前期)最大，当雌激素水平较低(发情前)时最小(发情)。在被训练为逃避阴道扩张的大鼠中，在自体子宫移植(n=9)或腹部脂肪移植(n=6)之前和之后4个月的4天发情周期中，测量了大鼠对不同扩张量的逃避反应百分比。还测量了阴道压力。在接受子宫但不是脂肪自体移植的大鼠中，逃逸百分比在手术后2个月内增加，然后趋于平稳。发情前期增加最大，发情期次之。所有组的阴道压力都没有变化。这些结果有力地支持了阴道痛敏依赖于包囊的假说。由于包囊位于远离阴道的部位，痛觉过敏涉及内脏-内脏的相互作用，可能是中枢调节的，而发情调节可能涉及对包囊的激素作用，或者更可能是对阴道传入纤维和/或中枢神经元的激素作用。(C)2003 Elsevier Inc.保留所有权利。
A rat model of endometriosis, in which pieces of uterine horn (versus fat in controls) are autotransplanted into the abdomen where they form cysts, reduces fecundity and produces vaginal hyperalgesia. The cysts gradually enlarge over a 2-month period postsurgically and then plateau. Cysts regress with low estrogen levels and reappear when they rise. Based on the hypothesis that the vaginal hyperalgesia depends upon the cysts, this study tested two predictions: that (1) the hyperalgesia would develop postsurgically in parallel with the cysts, and (2) the hyperalgesia would vary with estrous, being greatest when estrogen levels are high (proestrus) and least when low (estrus). In rats trained to escape vaginal distention, percentage escape responses to different distention volumes were measured across the rat's 4-day estrous cycle for 2.5 months before and up to 4 months after autotransplantation of uterus (n = 9) or fat (n = 6) in abdominal sites. Vaginal pressures were also measured. In rats with uterine but not fat autotransplants, escape percentages increased postsurgically over a 2-month period and then plateaued. The increase was greatest in proestrus and failed to occur in estrus. Vaginal pressures were unchanged in all groups. These results strongly support the hypothesis that the vaginal hyperalgesia depends upon the cysts. Because the cysts were located in sites remote from the vagina, the hyperalgesia involves viscero-visceral interactions and is likely centrally mediated, whereas the estrous modulation could involve hormonal actions either on the cysts or, more likely, on vaginal afferent fibers, and/or on central neurons. (C) 2003 Elsevier Inc. All rights reserved.