Ultrastructure of the placenta of antarctic seals during the first third of pregnancy

Akhouri A Sinha, Albert W. Erickson

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

The chorioallantoic placenta from six crabeater seals (Lobodon carcinophagus) with fetuses from 15–180 mm crown rump length (CRL), and two leopard seals (Hydrurga leptonyx) with fetuses 76 and 86 mm CRL was lobulated, zonary, labyrinthine and endotheliochorial. The fine structure of the placenta was essentially similar in both species. Maternal capillaries of the labyrinth had attenuated endothelial cells unlike the fissiped carnivores. They were surrounded by an outer syncytiotrophoblast, incomplete inner cytotrophoblast, and a core of mesenchymal tissue containing fetal vessels. In general, the cytotrophoblastic cells were less electron‐opaque than the syncytium; the former possessed abundant free ribosomes, while the latter had many nuclei, mitochondria, and numerous strands of rough endoplasmic reticulum. Mitotic figures were observed only in the cytotrophoblast. Plasma membranes between the trophoblastic layers had interdigitating processes which showed many desmosomes along the intercellular spaces, whereas membranes surrounding the maternal capillaries were usually smooth. In the limb‐bud stage embryo, the syncytiotrophoblast had thick and thin areas which became progressively attenuated in older fetuses. Instances of intratrophoblastic fetal capillaries were observed in seals with fetuses of 40 mm CRL and older, with consequent greatly thinned placental barriers. By Perl's reactions, Turnbull's method, and electron microscopy, rows of granular bodies positive for iron were demonstrated along the basement membrane of the trophoblastic cells and in the mesenchymal cells of the crabeater seals, but not the leopard seals. Furthermore, it is suggested that the deposits of granular bodies show the sites of iron storage in the placentas. In the limb‐bud stage embryo the hematome borders and isolated pouches of the central hematome were observed. The central hematome was antimesometrial. The hematomes were lined by columnar cytotrophoblastic cells which phagocytized extravasated maternal blood and absorbed histiotrophic material.

Original languageEnglish (US)
Pages (from-to)263-279
Number of pages17
JournalAmerican Journal of Anatomy
Volume141
Issue number2
DOIs
StatePublished - Jan 1 1974

Fingerprint

Placenta
Trophoblasts
Crown-Rump Length
Fetus
Pregnancy
Panthera
Mothers
Embryonic Structures
Iron
Desmosomes
Rough Endoplasmic Reticulum
Extracellular Space
Inner Ear
Giant Cells
Ribosomes
Basement Membrane
Electron Microscopy
Mitochondria
Endothelial Cells
Cell Membrane

Cite this

Ultrastructure of the placenta of antarctic seals during the first third of pregnancy. / Sinha, Akhouri A; Erickson, Albert W.

In: American Journal of Anatomy, Vol. 141, No. 2, 01.01.1974, p. 263-279.

Research output: Contribution to journalArticle

Sinha, Akhouri A ; Erickson, Albert W. / Ultrastructure of the placenta of antarctic seals during the first third of pregnancy. In: American Journal of Anatomy. 1974 ; Vol. 141, No. 2. pp. 263-279.
@article{a0ca77a8eda446f88fbf1a31f7b0bca2,
title = "Ultrastructure of the placenta of antarctic seals during the first third of pregnancy",
abstract = "The chorioallantoic placenta from six crabeater seals (Lobodon carcinophagus) with fetuses from 15–180 mm crown rump length (CRL), and two leopard seals (Hydrurga leptonyx) with fetuses 76 and 86 mm CRL was lobulated, zonary, labyrinthine and endotheliochorial. The fine structure of the placenta was essentially similar in both species. Maternal capillaries of the labyrinth had attenuated endothelial cells unlike the fissiped carnivores. They were surrounded by an outer syncytiotrophoblast, incomplete inner cytotrophoblast, and a core of mesenchymal tissue containing fetal vessels. In general, the cytotrophoblastic cells were less electron‐opaque than the syncytium; the former possessed abundant free ribosomes, while the latter had many nuclei, mitochondria, and numerous strands of rough endoplasmic reticulum. Mitotic figures were observed only in the cytotrophoblast. Plasma membranes between the trophoblastic layers had interdigitating processes which showed many desmosomes along the intercellular spaces, whereas membranes surrounding the maternal capillaries were usually smooth. In the limb‐bud stage embryo, the syncytiotrophoblast had thick and thin areas which became progressively attenuated in older fetuses. Instances of intratrophoblastic fetal capillaries were observed in seals with fetuses of 40 mm CRL and older, with consequent greatly thinned placental barriers. By Perl's reactions, Turnbull's method, and electron microscopy, rows of granular bodies positive for iron were demonstrated along the basement membrane of the trophoblastic cells and in the mesenchymal cells of the crabeater seals, but not the leopard seals. Furthermore, it is suggested that the deposits of granular bodies show the sites of iron storage in the placentas. In the limb‐bud stage embryo the hematome borders and isolated pouches of the central hematome were observed. The central hematome was antimesometrial. The hematomes were lined by columnar cytotrophoblastic cells which phagocytized extravasated maternal blood and absorbed histiotrophic material.",
author = "Sinha, {Akhouri A} and Erickson, {Albert W.}",
year = "1974",
month = "1",
day = "1",
doi = "10.1002/aja.1001410208",
language = "English (US)",
volume = "141",
pages = "263--279",
journal = "Developmental Dynamics",
issn = "1058-8388",
publisher = "Wiley-Liss Inc.",
number = "2",

}

TY - JOUR

T1 - Ultrastructure of the placenta of antarctic seals during the first third of pregnancy

AU - Sinha, Akhouri A

AU - Erickson, Albert W.

PY - 1974/1/1

Y1 - 1974/1/1

N2 - The chorioallantoic placenta from six crabeater seals (Lobodon carcinophagus) with fetuses from 15–180 mm crown rump length (CRL), and two leopard seals (Hydrurga leptonyx) with fetuses 76 and 86 mm CRL was lobulated, zonary, labyrinthine and endotheliochorial. The fine structure of the placenta was essentially similar in both species. Maternal capillaries of the labyrinth had attenuated endothelial cells unlike the fissiped carnivores. They were surrounded by an outer syncytiotrophoblast, incomplete inner cytotrophoblast, and a core of mesenchymal tissue containing fetal vessels. In general, the cytotrophoblastic cells were less electron‐opaque than the syncytium; the former possessed abundant free ribosomes, while the latter had many nuclei, mitochondria, and numerous strands of rough endoplasmic reticulum. Mitotic figures were observed only in the cytotrophoblast. Plasma membranes between the trophoblastic layers had interdigitating processes which showed many desmosomes along the intercellular spaces, whereas membranes surrounding the maternal capillaries were usually smooth. In the limb‐bud stage embryo, the syncytiotrophoblast had thick and thin areas which became progressively attenuated in older fetuses. Instances of intratrophoblastic fetal capillaries were observed in seals with fetuses of 40 mm CRL and older, with consequent greatly thinned placental barriers. By Perl's reactions, Turnbull's method, and electron microscopy, rows of granular bodies positive for iron were demonstrated along the basement membrane of the trophoblastic cells and in the mesenchymal cells of the crabeater seals, but not the leopard seals. Furthermore, it is suggested that the deposits of granular bodies show the sites of iron storage in the placentas. In the limb‐bud stage embryo the hematome borders and isolated pouches of the central hematome were observed. The central hematome was antimesometrial. The hematomes were lined by columnar cytotrophoblastic cells which phagocytized extravasated maternal blood and absorbed histiotrophic material.

AB - The chorioallantoic placenta from six crabeater seals (Lobodon carcinophagus) with fetuses from 15–180 mm crown rump length (CRL), and two leopard seals (Hydrurga leptonyx) with fetuses 76 and 86 mm CRL was lobulated, zonary, labyrinthine and endotheliochorial. The fine structure of the placenta was essentially similar in both species. Maternal capillaries of the labyrinth had attenuated endothelial cells unlike the fissiped carnivores. They were surrounded by an outer syncytiotrophoblast, incomplete inner cytotrophoblast, and a core of mesenchymal tissue containing fetal vessels. In general, the cytotrophoblastic cells were less electron‐opaque than the syncytium; the former possessed abundant free ribosomes, while the latter had many nuclei, mitochondria, and numerous strands of rough endoplasmic reticulum. Mitotic figures were observed only in the cytotrophoblast. Plasma membranes between the trophoblastic layers had interdigitating processes which showed many desmosomes along the intercellular spaces, whereas membranes surrounding the maternal capillaries were usually smooth. In the limb‐bud stage embryo, the syncytiotrophoblast had thick and thin areas which became progressively attenuated in older fetuses. Instances of intratrophoblastic fetal capillaries were observed in seals with fetuses of 40 mm CRL and older, with consequent greatly thinned placental barriers. By Perl's reactions, Turnbull's method, and electron microscopy, rows of granular bodies positive for iron were demonstrated along the basement membrane of the trophoblastic cells and in the mesenchymal cells of the crabeater seals, but not the leopard seals. Furthermore, it is suggested that the deposits of granular bodies show the sites of iron storage in the placentas. In the limb‐bud stage embryo the hematome borders and isolated pouches of the central hematome were observed. The central hematome was antimesometrial. The hematomes were lined by columnar cytotrophoblastic cells which phagocytized extravasated maternal blood and absorbed histiotrophic material.

UR - http://www.scopus.com/inward/record.url?scp=0016277941&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0016277941&partnerID=8YFLogxK

U2 - 10.1002/aja.1001410208

DO - 10.1002/aja.1001410208

M3 - Article

VL - 141

SP - 263

EP - 279

JO - Developmental Dynamics

JF - Developmental Dynamics

SN - 1058-8388

IS - 2

ER -