Establishment of uteroplacental circulation.

نویسنده

  • R Pijnenborg
چکیده

Haemochorial placentation, as it occurs in the human and other primate and rodent species, requires a connection of the placenta with supplying maternal (uteroplacental) arteries. Very little is known of the initial stages but endovascular trophoblast invasion seems to represent an essential element for further elaboration of an adequate uteroplacental circulation. In the human, endovascular trophoblast arrives in myometrial segments of spiral arteries only from about 15 weeks of pregnancy. This is preceded by an interstitial type of cytotrophoblast invasion which seems to be associated with regressive changes in spiral artery walls. It is possible that the latter forms an essential priming factor to allow subsequent endovascular migration. Endovascular trophoblast invasion has been documented in different laboratory animals, including the rat and the golden hamster. Especially in the latter case a sequence of changes in the maternal component, i.e. the maternal cellular elements in the spiral artery walls, precede the arrival of trophoblast. Besides, there is also some evidence of haemodynamical factor(s) influencing trophoblast migration. Because of the importance of this phenomenon in the establishment of an adequate uteroplacental circulation, it is essential to develop further experimental models for studying pathological situations as exist in human pregnancy.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Single bolus compared with a fractionated dose injection technique of bupivacaine for extradural Caesarean section: effect on uteroplacental and fetal haemodynamic state.

We studied 26 healthy parturients undergoing elective Caesarean section, allocated randomly to receive extradural block with 0.5% plain bupivacaine in a double-blind manner in either a single bolus or fractionated doses. After a 3-ml test dose, an additional 20 ml of bupivacaine were given over a 5-min period in the single bolus group (n = 13) and over a 25-min period in the fractionated dose g...

متن کامل

اثر متفورمین بر بهبود جریان خون رحمی- جفتی و کاهش عوارض حاملگی در خانم‌های حامله مبتلا به سندرم تخمدان پلی‌کیستی

Background: Some complications of pregnancy such as abortion, gestational diabetes mellitus, preeclampsia, and preterm delivery are more common among women with polycystic ovary syndrome (PCOS). Recently it has been reported that metformin treatment during pregnancy reduces pregnancy complications, so this study was conducted to demonstrate the possible effects of metformin on the uteroplacenta...

متن کامل

Surgery for the obstetrical patient

Each year approximately 50,000 women require surgery during pregnancy. It is the purpose of this paper to review the anatomical and physiological changes which occur during pregnancy, and to review the effects of anesthetics on the embryo and fetus. The indirect effects of anesthetic drugs and procedures on the uteroplacental circulation, and the practical considerations for the pregnant patien...

متن کامل

Autumn Rainfall Anomalies and Regional Atmospheric Circulation along Establishment of Weak La Nina after Strong El Nino in Iran

To study the Iran precipitation anomaly in September to November of 2016 and its probable connection with ENSO (El Nino-Southern Oscillation). This period with similar cases in the previous 55 years (1964, 1983, and 1995 according to forecasting center of NOAA) was investigated. In all cases, ENSO changed from strong El-Nino to weak La-Nina after a very brief neutral period. In the following, o...

متن کامل

The uteroplacental prolactin family and pregnancy.

The establishment and maintenance of pregnancy requires significant modifications of the maternal environment. During pregnancy, changes arise in virtually every major organ system within the mother, permitting growth and development of the embryo/fetus within the protected confines of the maternal reproductive tract. These gestational-dependent adaptations are believed to be controlled, at lea...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Reproduction, nutrition, developpement

دوره 28 6B  شماره 

صفحات  -

تاریخ انتشار 1988