The effects of the components of the renin-angiotensin system on the isolated perfused human placental cotyledon

D. G. Glance, M. G. Elder, D. L. Bloxam, L. Myatt

Research output: Contribution to journalArticle

57 Scopus citations


Angiotensins I, II, and III, renin substrate, and des-Asp1-angiotensin I were injected as a bolus into either the maternal or fetal circulation of human placental cotyledons perfused in vitro. All drugs tested produced dose-related increments in fetal perfusion pressure when injected into the fetal circulation, with the order of potency being angiotensin I ≈ angiotensin II ≈ angiotensin III ≳ des-Asp1-angiotensin I ≳ renin substrate. The responses to all the drugs could be blocked by the competitive inhibitor of angiotensin II, (Sar1, Ala8)-angiotensin II, but only the actions of angiotensin I, renin substrate, and des-Asp1-angiotensin I could be blocked by angiotensin converting enzyme inhibitor. When the agents were injected into the maternal circulation, only angiotensins II and III caused dose-related increments in fetal perfusion pressure. Possibly, the placenta may be the main site of conversion of angiotensin I to angiotensin II in the fetoplacental unit, and angiotensin II produced by the placenta could act locally to control fetoplacental blood flow.

Original languageEnglish (US)
Pages (from-to)450-454
Number of pages5
JournalAmerican journal of obstetrics and gynecology
Issue number4
StatePublished - Jun 15 1984


ASJC Scopus subject areas

  • Obstetrics and Gynecology

Cite this