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. 1969 Jun;202(2):471–481. doi: 10.1113/jphysiol.1969.sp008821

Maternal placental and myometrial blood flow in the pregnant rabbit

Sheila L B Duncan, B V Lewis
PMCID: PMC1351492  PMID: 5784297

Abstract

1. In anaesthetized rabbits 27-29 days pregnant (term is 31 days) uterine blood flow was measured in an extracorporeal loop between a carotid and the central end of an external iliac artery, the descending aorta and its other branches being tied. Mean flow was 45 ± 2 ml. min-1, or 105 ± 4 ml. min-1 per kg uterus and contents in thirty-four litters.

2. The partition of uterine blood flow to placentas (∼ 60%), myometrium (∼ 27%) and vagina (∼ 13%) as estimated by injection of isotopelabelled microspheres of 35 or 50 μ diameter, was similar in intact rabbits and in those with an extracorporeal loop.

3. Maternal blood flow was greater to the placentas of larger foetuses both absolutely and per unit placental weight. Flow to the placentas of dead foetuses was much less than to those of live foetuses, but flow to the adjacent myometrium was not decreased.

4. Maternal hypoxaemia (Pa, O2 ∼ 40 mm Hg) caused vasoconstriction in the uterine vascular bed after 3-4 min. The distribution of blood flow within the uterus was altered, the placental fraction falling to 32%. This was unaffected by carotid denervation.

5. These observations suggest that there are large differences in the physiological control of maternal blood flow to the placenta, myometrium and vagina.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Aherne W., Dunnill M. S. Morphometry of the human placenta. Br Med Bull. 1966 Jan;22(1):5–8. doi: 10.1093/oxfordjournals.bmb.a070437. [DOI] [PubMed] [Google Scholar]
  2. BARRON D. H., MESCHIA G. A comparative study of the exchange of the respiratory gases across the placenta. Cold Spring Harb Symp Quant Biol. 1954;19:93–101. doi: 10.1101/sqb.1954.019.01.013. [DOI] [PubMed] [Google Scholar]
  3. Barcroft J., Herkel W., Hill S. The rate of blood flow and gaseous metabolism of the uterus during pregnancy. J Physiol. 1933 Jan 16;77(2):194–206. doi: 10.1113/jphysiol.1933.sp002963. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Campbell A. G., Dawes G. S., Fishman A. P., Hyman A. I., James G. B. The oxygen consumption of the placenta and foetal membranes in the sheep. J Physiol. 1966 Jan;182(2):439–464. doi: 10.1113/jphysiol.1966.sp007831. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Dawes G. S., Lewis B. V., Milligan J. E., Roach M. R., Talner N. S. Vasomotor responses in the hind limbs of foetal and new-born lambs to asphyxia and aortic chemoreceptor stimulation. J Physiol. 1968 Mar;195(1):55–81. doi: 10.1113/jphysiol.1968.sp008446. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Longo L. D., Schwarz R. H., Forster R. E., 2nd O2 tensions of blood from uterine wall venules, maternal placental venules, and uterine vein. J Appl Physiol. 1968 Jun;24(6):787–791. doi: 10.1152/jappl.1968.24.6.787. [DOI] [PubMed] [Google Scholar]
  7. Makowski E. L., Meschia G., Droegemueller W., Battaglia F. C. Distribution of uterine blood flow in the pregnant sheep. Am J Obstet Gynecol. 1968 Jun 1;101(3):409–412. doi: 10.1016/0002-9378(68)90074-4. [DOI] [PubMed] [Google Scholar]
  8. Neutze J. M., Wyler F., Rudolph A. M. Use of radioactive microspheres to assess distribution of cardiac output in rabbits. Am J Physiol. 1968 Aug;215(2):486–495. doi: 10.1152/ajplegacy.1968.215.2.486. [DOI] [PubMed] [Google Scholar]
  9. Phibbs R. H., Wyler F., Neutze J. Rheology of microspheres injected into circulation of rabbits. Nature. 1967 Dec 30;216(5122):1339–1340. doi: 10.1038/2161339a0. [DOI] [PubMed] [Google Scholar]
  10. Power G. G., Longo L. D., Wagner N., Jr, Kuhl D. E., Forster R. E., 2nd Uneven distribution of maternal and fetal placental blood flow, as demonstrated using macroaggregates, and its response to hypoxia. J Clin Invest. 1967 Dec;46(12):2053–2063. doi: 10.1172/JCI105693. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Rudolph A. M., Heymann M. A. The circulation of the fetus in utero. Methods for studying distribution of blood flow, cardiac output and organ blood flow. Circ Res. 1967 Aug;21(2):163–184. doi: 10.1161/01.res.21.2.163. [DOI] [PubMed] [Google Scholar]
  12. WYNN R. M., DAVIES J. COMPARATIVE ELECTRON MICROSCOPY OF THE HEMOCHORIAL PLACENTA. Am J Obstet Gynecol. 1965 Feb 15;91:533–549. doi: 10.1016/0002-9378(65)90126-2. [DOI] [PubMed] [Google Scholar]

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