Regionale Unterschiede der alkalischen Phosphataseaktivit�t innerhalb der maternofetalen Str�mungseinheiten (Placentone) der reifen menschlichen Placenta (Histochemische und biochemische Untersuchungen)

Schuhmann, R.; Borst, R. H.; Lehmann, W. D.; Bäumler, U.; Tiedemann, U.

doi:10.1007/bf00668116

Cited by 8 publications

(7 citation statements)

References 6 publications

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“…II) in which identical quantities (0.5 mg) of microsomal fractions were incubated, show, however, that the quantitative factor plays a subordinate role ? Here also the conversion rate of peripheral tissue is significantly higher. Activities of -hydroxysteroid-oxidoreductase and the aromatising enzyme-system, which vary regionally within the placentone, correspond well to histochemical and biochemical findings about the activity of alkaline phosphatase [9] and glucose-6-phosphatedehydrögenase (our own, not yet published investigations). These, likewise, showed significantly lower quantities in placentone-centers.…”

Section: Resultssupporting

confidence: 84%

“…Histochemical and biochemical studies on activity of alkaline phosphatase [9] demonstrated varied activity, which corresponds to morphological findings; central •villi behaved like villi from placentas of pregnancies in the Ist and 2nd trimester. In this work we therefore tried to determine whether enzymes of steroid-biosynthesis (17/-hydroxysteroidoxidoreductase and the aromatising enzyme System) also :show regional differences in respect to their specific activity.…”

Section: Discussionmentioning

confidence: 52%

“…Histochemical and biochemical investigations [9] revealed results corresponding to the morphological findings, that is regionally difFerentiated activity of alkaline phosphatase. They showed that centrally situated villi, which demonstrate a lower degree of maturity than peripherally situated ones, also reacted like less mature villi in respect to activity of alkaline phosphatase.…”

mentioning

confidence: 65%

“…I, (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) Q J 4 -androstendione was incubated with microsomal fraction (equivalent to 0.5 g fresh weight) from 12 placentones of 8 placentas. Each incubation took place with a subcellular fraction from the center and then from the periphery of the placentones, so that a direct comparison was possible in each placenta.…”

Section: Resultsmentioning

confidence: 99%

“…All incubations took place in SOERENSON phosphate buffer (pH 7.35) at 37°C, open to the air in a shaking thermostat. In every case 250 nC (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) Q A f Androstendione (specific activity 60mC/mMol) was dissolved with 0.5 ml microsomal fraction (equivalent to 0.5 g fresh weight placenta) or with 0.5 mg of microsomal fraction and with an NADPH-generating System in 3 ml of 0.15 M SOERENSON phosphate buffer. After 5 minutes incubation, extraction of Solutions was performed 3 times with ether/chloroform (3:1).…”

Section: C) 4 -Androstendionementioning

confidence: 99%

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Regionally different stetoid-biosynthesis within materno-fetal circulation units (placentones) of mature human placentas

Lehmann¹,

Schuhmann²,

Kraus³

1973

Journal of Perinatal Medicine

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Earlier studies [8] demonstrated the morphological differences between chorionic villi of central and peripheral regions in placentones. Histochemical and biochemical investigations [9] revealed results corresponding to the morphological findings, that is regionally difFerentiated activity of alkaline phosphatase. They showed that centrally situated villi, which demonstrate a lower degree of maturity than peripherally situated ones, also reacted like less mature villi in respect to activity of alkaline phosphatase. The purpose of this paper is to examine whether enzymes of steroid-biosynthesis also demonstrate regional differences concerning their own specific activities. This concerns, above all, aromatising enzyme Systems and 17ß-hydroxysteroid-oxidoreductase. For this reason, we measured the in vitro transformation of 2d-4-androstendione to testosterone and to oestrone/oestradiol-17j8 by microsomes fromtissue of central and peripheral regions of the placentone. Material and Methods TissueEight placentas were used from clinically uncomplicated pregnancies, which ended in spontaneous deliveries between the 38th and 40th weck of pregnancy. Weight of newborns was normal, ApGAR-scores were never under 9. Germany. 1961 Medical Doctor. 1963-1966 Membranes and blood were removed immediately post partum and placentas were cut into 2 cm wide sections vertically to the maternal surface. With the help of a dissecting lens we took biopsies from .central ^ad.,peripheraLareas-of •plaGentones^ekuäted in the middle portion of the placenta. Tissue was then homogenized in 0.25 M sucrose in a glass homogenisator. (The method has been described elsewhere [5].) Remains of connective tissue which coüld not be homogenized were * Investigations were supported by the Forschungsgemeinschaft". "Deutsche J. Perinat. Mcd. l (1973) Curriculum vitae WOLF DIETRICH LEHMANN, M. D. born in 1935 in Kielj

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Section: Resultssupporting

confidence: 84%

Section: Discussionmentioning

confidence: 52%

mentioning

confidence: 65%

Section: Resultsmentioning

confidence: 99%

Section: C) 4 -Androstendionementioning

confidence: 99%

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Regionally different stetoid-biosynthesis within materno-fetal circulation units (placentones) of mature human placentas

Lehmann¹,

Schuhmann²,

Kraus³

1973

Journal of Perinatal Medicine

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Enzymhistochemische Untersuchungen an reifen menschlichen Placentazotten

et al. 1974

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�ber die Gliederung der reifen menschlichen Placenta

Schubert

1977

Arch. Gynak.

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By means of macroscopic, histologic and enzyme histochemical methods the concept of Schuhmann and Wehler (1971) that the mature human placenta shows a morphological organization coincides with bloodflow-units was examined. The investigation deals with the existence and distribution of terminal villi which can be distinguished on the basis of histological and enzyme histochemical peculiarities. 90 placentas were available, 3 of which were premature. In 6 cases one half of the placenta or the whole organ was cut into serial sections. Mature placentas. Per dissected placenta on an average 6--7 regions with cavities in the intervillous space could be observed, which might correlate to the "placentones" postulated by Schuhmann and Wehler (1971). Using histological techniques at random scattered areas of different size of so-called "immature" villi exist in the near of the basal plate; a relation between these areas and the placentones cannot be seen. All enzymes investigated possess a lower activity in the syncytiotrophoblast of the immature villi than in the mature ones. The demonstration of phosphatases and lysosomal enzymes reveals groups of mature villi with increased activity; they form a patchy enzyme pattern. With the exception of dehydrogenases there is no relation between villi with special enzyme activities and the placentones. Premature placentas. The younger the placenta, the larger is the volume of immature villi. Result. At present a organization of the human placenta into morphological units which correlates to the bloodflow (placentones) cannot be seen. A principle of segmentation which bases on differences between the terminal villi cannot be demonstrated.

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Regionale Unterschiede der alkalischen Phosphataseaktivit�t innerhalb der maternofetalen Str�mungseinheiten (Placentone) der reifen menschlichen Placenta (Histochemische und biochemische Untersuchungen)

Cited by 8 publications

References 6 publications

Regionally different stetoid-biosynthesis within materno-fetal circulation units (placentones) of mature human placentas

Regionally different stetoid-biosynthesis within materno-fetal circulation units (placentones) of mature human placentas

Enzymhistochemische Untersuchungen an reifen menschlichen Placentazotten

�ber die Gliederung der reifen menschlichen Placenta

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