Fletcher J E, Thomas T A, Hill R G
Life Sci. 1983;33 Suppl 1:515-8. doi: 10.1016/0024-3205(83)90554-4.
The role of opioid peptides during pregnancy and parturition has not been defined. They may function as natural analgesics during parturition. Pain thresholds were tested during pregnancy but, in contrast with a previous study, were found not to change. Plasma Beta-endorphin-like-immunoreactivity (B-ELI) was measured and towards the end of pregnancy a significant increase was recorded. Peptide levels returned to the pre-gestational concentration just prior to parturition. Pituitary B-ELI was also measured and was only significantly raised on the day before expected parturition. These changes add to the evidence that opioid peptides have a physiological function during pregnancy and parturition.
阿片肽在妊娠和分娩过程中的作用尚未明确。它们可能在分娩时起到天然止痛剂的作用。研究人员在孕期对疼痛阈值进行了测试，但与之前的一项研究不同，此次研究发现疼痛阈值并未发生变化。研究人员测量了血浆中β-内啡肽样免疫反应性（B-ELI），在妊娠末期记录到其显著升高。在临产前，肽水平恢复到孕前浓度。研究人员还测量了垂体B-ELI，结果显示仅在预期分娩前一天显著升高。这些变化进一步证明了阿片肽在妊娠和分娩过程中具有生理功能。
