McLaughlin M K, Keve T M, Cooke R
Department of Obstetrics and Gynecology, University of Vermont College of Medicine, Burlington 05405.
Am J Obstet Gynecol. 1989 Jan;160(1):47-53. doi: 10.1016/0002-9378(89)90085-9.
Four pregnant and four castrated ewes were chronically instrumented for the measurement of external iliac blood flow to test the hypothesis that pregnancy alters alpha-adrenergic sensitivity in a major regional circulation. Complete dose-response curves were generated to methoxamine, phenylephrine, and norepinephrine. Pregnancy was associated with no change in methoxamine sensitivity, an increase in phenylephrine sensitivity, and a decrease in norepinephrine sensitivity. These differential changes in drug sensitivity suggest (1) the alpha 1-receptor population is functionally similar between the two groups of animals, (2) uptake 1 is inhibited, and (3) either catechol-O-methyltransferase activity is increased or the alpha 2- or beta-receptor population changes in this circulation during pregnancy. These data illustrate the complexity of the change in the adrenergic system during pregnancy.
四只怀孕母羊和四只去势母羊被长期植入仪器以测量髂外血流量，以检验妊娠会改变主要区域循环中α-肾上腺素能敏感性这一假设。生成了对甲氧明、去氧肾上腺素和去甲肾上腺素的完整剂量反应曲线。妊娠与甲氧明敏感性无变化、去氧肾上腺素敏感性增加和去甲肾上腺素敏感性降低有关。药物敏感性的这些差异变化表明：（1）两组动物之间α1受体群体在功能上相似；（2）摄取1受到抑制；（3）在妊娠期间，该循环中儿茶酚-O-甲基转移酶活性增加，或者α2或β受体群体发生变化。这些数据说明了妊娠期间肾上腺素能系统变化的复杂性。
