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Research Article Free access | 10.1172/JCI105693
Department of Physiology, Graduate Division, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Obstetrics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Gynecology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiological Science, the Johns Hopkins University School of Medicine, Baltimore, Maryland
‡Postdoctoral fellow of the National Institutes of Health.
§Recipient of a USPHS Research Career Development Award HD-23,676.
Address requests for reprints to Dr. Lawrence D. Longo, Department of Physiology, Graduate Division, School of Medicine, University of Pennsylvania, Philadelphia, Pa. 19104.
ǁRecipient of a USPHS Research Career Progress Award CA-14,020.
*Received for publication 10 January 1967 and in revised form 7 August 1967.
This work was presented in part at the Annual Meeting of the American Society for Clinical Investigation in Atlantic City, N. J., 2 May 1966, and was supported by grant No. HD-1860 from the National Institute of Child Health and Human Development; Training grant-5430; Grants No. C-4456 and GM-10548 from the National Institute of General Medical Sciences and grants from the Life Insurance Medical Research Fund and the Josiah Macy Jr., Foundation.
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Department of Physiology, Graduate Division, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Obstetrics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Gynecology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiological Science, the Johns Hopkins University School of Medicine, Baltimore, Maryland
‡Postdoctoral fellow of the National Institutes of Health.
§Recipient of a USPHS Research Career Development Award HD-23,676.
Address requests for reprints to Dr. Lawrence D. Longo, Department of Physiology, Graduate Division, School of Medicine, University of Pennsylvania, Philadelphia, Pa. 19104.
ǁRecipient of a USPHS Research Career Progress Award CA-14,020.
*Received for publication 10 January 1967 and in revised form 7 August 1967.
This work was presented in part at the Annual Meeting of the American Society for Clinical Investigation in Atlantic City, N. J., 2 May 1966, and was supported by grant No. HD-1860 from the National Institute of Child Health and Human Development; Training grant-5430; Grants No. C-4456 and GM-10548 from the National Institute of General Medical Sciences and grants from the Life Insurance Medical Research Fund and the Josiah Macy Jr., Foundation.
Find articles by Longo, L. in: JCI | PubMed | Google Scholar
Department of Physiology, Graduate Division, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Obstetrics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Gynecology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiological Science, the Johns Hopkins University School of Medicine, Baltimore, Maryland
‡Postdoctoral fellow of the National Institutes of Health.
§Recipient of a USPHS Research Career Development Award HD-23,676.
Address requests for reprints to Dr. Lawrence D. Longo, Department of Physiology, Graduate Division, School of Medicine, University of Pennsylvania, Philadelphia, Pa. 19104.
ǁRecipient of a USPHS Research Career Progress Award CA-14,020.
*Received for publication 10 January 1967 and in revised form 7 August 1967.
This work was presented in part at the Annual Meeting of the American Society for Clinical Investigation in Atlantic City, N. J., 2 May 1966, and was supported by grant No. HD-1860 from the National Institute of Child Health and Human Development; Training grant-5430; Grants No. C-4456 and GM-10548 from the National Institute of General Medical Sciences and grants from the Life Insurance Medical Research Fund and the Josiah Macy Jr., Foundation.
Find articles by Wagner, H. in: JCI | PubMed | Google Scholar
Department of Physiology, Graduate Division, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Obstetrics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Gynecology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiological Science, the Johns Hopkins University School of Medicine, Baltimore, Maryland
‡Postdoctoral fellow of the National Institutes of Health.
§Recipient of a USPHS Research Career Development Award HD-23,676.
Address requests for reprints to Dr. Lawrence D. Longo, Department of Physiology, Graduate Division, School of Medicine, University of Pennsylvania, Philadelphia, Pa. 19104.
ǁRecipient of a USPHS Research Career Progress Award CA-14,020.
*Received for publication 10 January 1967 and in revised form 7 August 1967.
This work was presented in part at the Annual Meeting of the American Society for Clinical Investigation in Atlantic City, N. J., 2 May 1966, and was supported by grant No. HD-1860 from the National Institute of Child Health and Human Development; Training grant-5430; Grants No. C-4456 and GM-10548 from the National Institute of General Medical Sciences and grants from the Life Insurance Medical Research Fund and the Josiah Macy Jr., Foundation.
Find articles by Kuhl, D. in: JCI | PubMed | Google Scholar
Department of Physiology, Graduate Division, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Obstetrics, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Gynecology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
Department of Radiological Science, the Johns Hopkins University School of Medicine, Baltimore, Maryland
‡Postdoctoral fellow of the National Institutes of Health.
§Recipient of a USPHS Research Career Development Award HD-23,676.
Address requests for reprints to Dr. Lawrence D. Longo, Department of Physiology, Graduate Division, School of Medicine, University of Pennsylvania, Philadelphia, Pa. 19104.
ǁRecipient of a USPHS Research Career Progress Award CA-14,020.
*Received for publication 10 January 1967 and in revised form 7 August 1967.
This work was presented in part at the Annual Meeting of the American Society for Clinical Investigation in Atlantic City, N. J., 2 May 1966, and was supported by grant No. HD-1860 from the National Institute of Child Health and Human Development; Training grant-5430; Grants No. C-4456 and GM-10548 from the National Institute of General Medical Sciences and grants from the Life Insurance Medical Research Fund and the Josiah Macy Jr., Foundation.
Find articles by Forster, R. in: JCI | PubMed | Google Scholar
Published December 1, 1967 - More info
A technique is described for studying the distribution of blood flow to the maternal and fetal placental vessels in sheep and dogs with radioactive labeled macroaggregates of albumin.
When the maternal animal breathed room air the distribution of maternal placental blood flow was uneven among the cotyledons as well as within a given cotyledon. Fetal blood flow was also distributed nonuniformly among and within the cotyledons. The relation of maternal to fetal placental blood flow was also markedly uneven (coefficient of correlation, τ = 0.066). After the animal was made hypoxic by breathing 10-12% O2 the distribution of maternal, fetal, and maternal/fetal placental flows became more uniform. The coefficient of correlation of maternal to fetal flow was high (τ = 0.53, P < 0.01). While the maternal animal breathed room air, after ligation of a major branch of the umbilical artery the distribution of maternal, fetal, and maternal/fetal flows in the remaining two-thirds to three-fourths of the placenta became more uniform. The correlation coefficient for maternal to fetal flow was high (τ = 0.35, P < 0.01).
It appears that under normal circumstances with uneven distribution of blood flows there is a considerable portion of the placenta that does not receive blood flow in optimum quantities to promote efficient O2 exchange. Failure to consider the influence of nonuniform maternal flow/fetal flow will result in overestimation of mean maternal-fetal oxygen tension gradients, and thus underestimation of the placental diffusing capacity for oxygen.
In response to maternal hypoxia or compromise of the fetal placental circulation the distribution of maternal, fetal, and maternal/fetal flows becomes more uniform, thereby increasing the efficiency of placental O2 exchange.
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