Ke R, Vohra M, Casper R
Am J Obstet Gynecol. 1984 Aug 15;149(8):841-4. doi: 10.1016/0002-9378(84)90601-x.
Regular, spontaneous contractions of human myometrial strips obtained at the time of elective cesarean section were recorded in a tissue bath in five experiments. Administration of the beta-adrenergic agonist isoproterenol (1 mumol/L) resulted in the rapid onset of myometrial relaxation. In the continuous presence of the beta-agonist, myometrial contractions of amplitude equal to or greater than that of baseline resumed after 10 to 40 minutes (mean +/- SEM = 29.7 +/- 7.3), indicating the development of desensitization of the tissue to the tocolytic effects of isoproterenol. In contrast, intermittent exposure of the myometrial strips to isoproterenol prevented the onset of desensitization and resulted in prolonged inhibition of myometrial contractions. These findings suggest that modification of the present regimen of administration of beta-adrenergic agonists from continuous to intermittent infusion may improve the success of these agents in the prevention of preterm births.
在五项实验中，对择期剖宫产时获取的人子宫肌条的规律性自发收缩进行了记录，记录是在组织浴中进行的。给予β-肾上腺素能激动剂异丙肾上腺素（1μmol/L）导致子宫肌迅速松弛。在持续存在β-激动剂的情况下，10至40分钟（平均值±标准误=29.7±7.3）后，振幅等于或大于基线的子宫肌收缩恢复，这表明组织对异丙肾上腺素的宫缩抑制作用产生了脱敏。相比之下，子宫肌条间歇性暴露于异丙肾上腺素可防止脱敏的发生，并导致子宫肌收缩的长期抑制。这些发现表明，将目前β-肾上腺素能激动剂的给药方案从持续输注改为间歇性输注可能会提高这些药物预防早产的成功率。
