Bryant-Greenwood G D, Tashima L, Greenwood F C, Taylor E, Peaker M
Department of Anatomy and Reproductive Biology, University of Hawaii, Honolulu 96822.
Endocrinology. 1991 Oct;129(4):2119-25. doi: 10.1210/endo-129-4-2119.
Mastectomy in the guinea pig increases the incidence of still births and neonatal deaths compared with intact animals. The guinea pig has the endometrial gland cells (EGC) as the major source of relaxin, and this hormone has possible roles in uterine quiescence, cervical dilatation, and lengthening of the interpubic ligament in pregnancy. An effect of mastectomy on uterine relaxin has been sought by immunocytochemical localization during the estrous cycle, mid and late pregnancy and on endometrial relaxin gene expression in the late pregnant mastectomized animal by Northern analysis. Endometrium from midpregnant (day 35) and late pregnant (day 63) and from lactating (days 5, 21, and 28) guinea pigs immunostained with antiserum to porcine relaxin by the avidinbiotin technique. By increasing the sensitivity of the latter, relaxin immunostaining was also detected for the first time in EGC from cyclic animals (days 9 and 14). A pattern and intensity of relaxin immunostaining could be readily assigned to each of the stages examined: estrous cycle, midpregnancy, late pregnancy, lactation, and post weaning. The dark uniform staining of the EGC in late pregnancy was followed by sporadic staining of the EGC in lactation, returning to the cyclic picture after weaning. Endometrium from mastectomized cyclic and late pregnant guinea pigs showed a reduction in the amount of immunostaining compared with the relevant control animals. The reduction was most pronounced in the mastectomized late pregnant guinea pig. This result was reflected in an apparently lower level of relaxin mRNA in the endometrium of these animals compared to intact controls. These data indicate a novel linkage between the mammary gland, either directly or indirectly, to the nonpregnant or pregnant uterus. The loss of this signal appears to be associated with subsequent problems at parturition which may be linked to the reduction in endometrial gland relaxin production. The nature of this signal from the mammary gland, normally considered to be an exocrine rather than an endocrine gland, is unknown.
与未切除乳腺的豚鼠相比，切除乳腺的豚鼠死产和新生儿死亡的发生率更高。豚鼠的子宫内膜腺细胞（EGC）是松弛素的主要来源，这种激素在孕期子宫静止、宫颈扩张和耻骨间韧带延长方面可能发挥作用。通过免疫细胞化学定位，研究了切除乳腺对发情周期、妊娠中期和晚期豚鼠子宫松弛素的影响，并通过Northern分析研究了切除乳腺的晚期妊娠豚鼠子宫内膜松弛素基因的表达。用抗猪松弛素抗血清通过抗生物素蛋白-生物素技术对妊娠中期（第35天）、晚期妊娠（第63天）和哺乳期（第5、21和28天）豚鼠的子宫内膜进行免疫染色。通过提高检测的灵敏度，首次在发情周期动物（第9天和第14天）的EGC中检测到松弛素免疫染色。可以很容易地确定每个检查阶段（发情周期、妊娠中期、晚期妊娠、哺乳期和断奶后）松弛素免疫染色的模式和强度。妊娠晚期EGC的深色均匀染色之后是哺乳期EGC的散在染色，断奶后恢复到发情周期的状态。与相关对照动物相比，切除乳腺的发情周期和晚期妊娠豚鼠的子宫内膜免疫染色量减少。这种减少在切除乳腺的晚期妊娠豚鼠中最为明显。这一结果反映在与完整对照相比，这些动物子宫内膜中松弛素mRNA水平明显较低。这些数据表明乳腺与未妊娠或妊娠子宫之间存在一种新的直接或间接联系。这种信号的丧失似乎与随后分娩时的问题有关，这可能与子宫内膜腺松弛素分泌减少有关。来自通常被认为是外分泌腺而非内分泌腺的乳腺的这种信号的性质尚不清楚。
