THE ULTRASTRUCTURE OF THE HUMAN GRANULOSAL LUTEIN CELL OF THE FIRST TRIMESTER OF GESTATION

1968 ◽  
Vol 58 (3) ◽  
pp. 481-496 ◽  
Author(s):  
Poul Hjortkjær Pedersen ◽  
Jørgen Falck Larsen
Keyword(s):  
Endoplasmic Reticulum ◽  
Smooth Endoplasmic Reticulum ◽  
First Trimester ◽  
Corpora Lutea ◽  
Steroid Synthesis ◽  
Intracellular Location ◽  
Human Pregnancy ◽  
Subendothelial Space ◽  
Lutein Cell ◽  
Early Human

ABSTRACT The ultrastructure of granulosal lutein cells of 13 corpora lutea in early human pregnancy was studied. The predominant cytoplasmic element was the smooth endoplasmic reticulum. No convincing signs of degeneration of the lutein cells could be demonstrated within the first 14 weeks of pregnancy, as the mitochondria as well as the rough and smooth endoplasmic reticulum were well preserved. However, lysosomes may be slightly more numerous in older specimens and the subendothelial space increases with the age of gestation. A particular type of multilaminated structure one to five micron in diameter was observed, particularly in the earliest specimens. The possible intracellular location of steroid synthesis is discussed.

PROPRANOLOL-BLOCKADE OF VASOPRESSIN INDUCED INCREASE IN PLASMA PROGESTERONE IN EARLY HUMAN PREGNANCY

1971 ◽  
Vol 66 (2) ◽  
pp. 283-288 ◽  
Author(s):  
Petter Fylling
Keyword(s):  
Cyclic Amp ◽  
Uterine Cervix ◽  
Adenosine Monophosphate ◽  
First Trimester ◽  
Blocking Agent ◽  
Simultaneous Administration ◽  
Plasma Progesterone ◽  
Human Pregnancy ◽  
Peripheral Plasma ◽  
Early Human

ABSTRACT Following continuous dilation of the uterine cervix or intravenous infusion of vasopressin during the first trimester of human pregnancy, a marked increase in the peripheral plasma progesterone levels was observed. This effect was blocked by simultaneous administration of propranolol (Inderal®), a β-blocking agent. It is suggested that both these stimulating and inhibiting effects might be related to 3′, 5′-adenosine monophosphate (cyclic AMP). The results indicate the existence of β-receptors in steroid producing tissues.

scholarly journals OVARIAN STEROID CELLS

1966 ◽  
Vol 31 (3) ◽  
pp. 501-516 ◽  
Author(s):  
E. Joan Blanchette
Keyword(s):  
Endoplasmic Reticulum ◽  
Granulosa Cell ◽  
Granulosa Cells ◽  
Follicle Cell ◽  
Staining Procedure ◽  
Steroid Synthesis ◽  
Cytoplasmic Matrix ◽  
Follicle Rupture ◽  
Lutein Cell ◽  
Glycogen Particles

The granulosa follicle cell of the Graafian follicle of the rabbit ovary differentiates into a lutein cell involved in steroid synthesis. Cytological events which occur within the granulosa cell of the normally stimulated follicle prior to ovulation have been duplicated by the intrafollicular injection of exogenous gonadotrophin. The luteinization of the granulosa cells involves the accumulation of 250- to 300-A, electron-opaque, spherical granules, dispersed within the cytoplasmic matrix, which have been identified as glycogen with the PAS-staining procedure. Further development of the granulosa cell following ovulation involves an increase in cell size, a decrease in the number of RNP particles, and an accumulation of an abundant system of intracellular membranes (agranular endoplasmic reticulum). Glycogen granules first appear in the granulosa cells as the separate, monoparticulate form. After follicle rupture and the formation of agranular endoplasmic reticulum, glycogen particles are present in a rosette arrangement within membrane-bounded vacuoles. The rosette arrangement of glycogen particles is also found dispersed within the cytoplasmic matrix of the lutein cell during the later stages of the cell life-span. Injection of luteinizing hormone or human chorionic gonadotrophin into a mature follicle also produces a marked accumulation of monoparticulate glycogen in the majority of granulosa cells, within 30 min. Cytoplasmic extensions which contain the glycogen masses are noticeably free of RNP particles.

PROGESTERONE AND HUMAN CHORIONIC GONADOTROPHIN (HCG) LEVELS IN PLASMA DURING DILATION OF THE UTERINE CERVIX IN EARLY HUMAN PREGNANCY

1970 ◽  
Vol 65 (2) ◽  
pp. 293-301 ◽  
Author(s):  
Petter Fylling ◽  
Nils Norman
Keyword(s):  
Plasma Level ◽  
Uterine Cervix ◽  
First Trimester ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Control Group ◽  
Human Pregnancy ◽  
Medial Side ◽  
The Mean ◽  
Early Human

ABSTRACT Dilation of the uterine cervix for 16 hours as a preliminary to the induction of legal abortion during the first trimester of human pregnancy resulted in a marked increase in the plasma level of both progesterone and human chorionic gonadotrophin (HCG). In a control group (with the dilating instrument taped on the medial side of the upper thigh) no increase in progesterone occurred. The increase in the plasma level of HCG was more pronounced than that of progesterone, the mean increase being 80 and 50 per cent respectively. Following the termination of the pregnancy, the half life (t½) of endogenous HCG in peripheral plasma could be calculated, and was found to be about 7 hours.

scholarly journals OBSERVATIONS ON THE FINE STRUCTURE OF LUTEIN CELLS

1962 ◽  
Vol 12 (1) ◽  
pp. 101-113 ◽  
Author(s):  
Allen C. Enders
Keyword(s):  
Electron Microscopy ◽  
Endothelial Cells ◽  
Endoplasmic Reticulum ◽  
Fine Structure ◽  
Steroid Hormones ◽  
Osmium Tetroxide ◽  
Secretory Activity ◽  
Corpora Lutea ◽  
Pericapillary Space ◽  
Lutein Cell

Corpora lutea from the period of delayed implantation and from early postimplantation stages of the armadillo, mink, and rat were fixed in buffered osmium tetroxide-sucrose or potassium permanganate. After rapid dehydration, the portions of the corpora lutea were embedded in either methacrylate or epoxy resin. Examination of the lutein cells by electron microscopy revealed the presence, in the better preserved material, of an extensive development of tubular agranular endoplasmic reticulum. Although the membranes of the endoplasmic reticulum are the most striking feature of the lutein cells of both stages of the three animals examined, very numerous large mitochondria with cristae that exhibit a variety of forms tending toward villiform, and protrusions and foldings of the lutein cell margins on the pericapillary space are also characteristic of these cells. Certain minor differences in the lutein cells of the species examined are also noted. No indications of conversion of mitochondria into lipid, of accumulation of lipid in the Golgi area, or of the protrusion of lutein cells into spaces between the endothelial cells, as suggested by other authors, were noted in these preparations. Some of the difficulties inherent in the visualization of the secretory activity of cells producing steroid hormones are briefly discussed.

THE CONVERSION OF DEHYDROEPIANDROSTERONE-7α-3H TO OESTROGENS BY CORPORA LUTEA OF EARLY HUMAN PREGNANCY

1967 ◽  
Vol 54 (1) ◽  
pp. 30-36 ◽  
Author(s):  
George L. Flickinger ◽  
Chung-Hsiu Wu ◽  
Joseph C. Touchstone
Keyword(s):  
Thin Layer ◽  
Early Pregnancy ◽  
Specific Activity ◽  
Corpora Lutea ◽  
Slice Preparation ◽  
Human Pregnancy ◽  
Specific Activities ◽  
Layer Chromatography ◽  
Early Human ◽  
Human Corpus Luteum

ABSTRACT Incubation of two corpora lutea of early human pregnancy in the presence of dehydroepiandrosterone-7α-3H resulted in a 33—44% yield of oestrone plus 17β-oestradiol. The major oestrogen formed in homogenate preparations was oestrone while in a slice preparation it was 17β-oestradiol. Oestrone and 17β-oestradiol were characterized by solvent partition, paper chromatography and crystallization to constant specific activity after addition of carrier. Acetates of the crystallized oestrogens had the same specific activities as the parent steroids and these derivatives were further identified by thin layer chromatography. These results suggest that dehydroepiandrosterone may serve as a major precursor for oestrogen biosynthesis by human corpus luteum of early pregnancy.

scholarly journals Developmental changes in localization of steroid synthesis enzymes in camelid placenta

Reproduction ◽  
2003 ◽  
pp. 239-247 ◽  
Author(s):  
FB Wooding ◽  
M Ozturk ◽  
JA Skidmore ◽  
WR Allen
Keyword(s):  
Endoplasmic Reticulum ◽  
Light Microscope ◽  
Smooth Endoplasmic Reticulum ◽  
Giant Cells ◽  
Developmental Changes ◽  
Side Chain ◽  
Steroid Synthesis ◽  
Similar Frequency ◽  
Chain Cleavage ◽  
Multinucleate Giant Cells

The uninucleate trophoblast of epitheliochorial camelid placenta produces multinucleate giant cells starting between day 30 and day 35 of pregnancy. The giant cells are found scattered along the trophoblast at similar frequency throughout gestation. Light microscope immunocytochemistry indicates that the four steroid synthesis enzymes (cholesterol side chain cleavage, 3beta-hydroxysteroid de-hydrogenase, 17alpha-hydroxylase and aromatase) are present in all uninucleate trophoblast cells between day 14 and day 30 of pregnancy, but are found only in the giant cells once they are established, and that this localization persists until term. The giant cells show massive amounts of smooth endoplasmic reticulum and numerous small mitochondria, again as has been shown in other steroid-producing cells. As progesterone from the corpus luteum is necessary throughout gestation in camels, the capacity for oestrogen production by the trophoblast presumably has an important role, but one limited mostly to the immediate vicinity of the fetomaternal interface.

scholarly journals Inhibin A and Activin A in the First Trimester of Human Pregnancy

1997 ◽  
Vol 82 (5) ◽  
pp. 1557-1560 ◽  
Author(s):  
Mary Birdsall ◽  
William Ledger ◽  
Nigel Groome ◽  
Hossam Abdalla ◽  
Shanthi Muttukrishna
Keyword(s):  
First Trimester ◽  
Activin A ◽  
Maternal Serum ◽  
Corpora Lutea ◽  
Specific Enzyme ◽  
Inhibin A ◽  
Human Pregnancy ◽  
First Trimester Of Pregnancy ◽  
Donor Egg ◽  
High Concentrations

Abstract Recent studies show that high concentrations of inhibin A and activin A are present in the maternal serum throughout human pregnancy. The aim of this study was to determine whether the corpus luteum produces significant quantities of inhibin A and activin A during the first trimester of pregnancy. This prospective study examined two groups of women who had blood samples taken from 5–12 weeks gestation. One group consisted of 14 women with donor egg pregnancies (8 singletons and 6 multiples) who did not have corpora lutea, and the other group consisted 5 women with spontaneous pregnancies who had corpora lutea. Inhibin A and activin A were measured at weekly intervals using specific enzyme immunoassays. All pregnancies progressed to term, with healthy babies being delivered. Maternal serum concentrations of inhibin A significantly increased throughout the study period in the donor egg pregnancies (P < 0.001) and the control pregnancies (P < 0.001). Circulating concentrations of activin A also increased significantly in both the spontaneous and donor egg pregnancies (P < 0.001) during the study period. However, the concentrations of inhibin A and activin A in the first trimester of human pregnancy were not significantly different in the women with or without corpora lutea, suggesting a fetoplacental origin. Multiple donor egg pregnancies were found to have higher concentrations of inhibin A (P < 0.001) and activin A (P < 0.05) compared with singleton donor egg pregnancies, which also supports a placental source.

Ultrastructure of Luteal Cells in Fully Formed and Regressing Corpora Lutea During Pregnancy and Lactation in the Marsupials Isoodon Macrourus and Perameles Nasuta.

1980 ◽  
Vol 28 (2) ◽  
pp. 195 ◽  
Author(s):  
DE Hollis ◽  
AG Lyne
Keyword(s):  
Endoplasmic Reticulum ◽  
Lipid Droplets ◽  
Smooth Endoplasmic Reticulum ◽  
Cell Junction ◽  
Corpora Lutea ◽  
Cholesterol Crystals ◽  
Luteal Cells ◽  
Pregnancy And Lactation ◽  
Advanced Stages ◽  
Spherical Nuclei

Corpora lutea (CL) collected from 23 bandicoots (I. macrourus and P. nasuta), from day 5 of pregnancy (gestation 12.5 days) to day 53 of lactation (lactation c. 60 days), were examined with the electron microscope. The luteal cells of fully formed CL (from day 5 of pregnancy to day 44 of lactation) were large and contained spherical nuclei with distinct nucleoli. The amount of heterochromatin increased during the latter part of this period. The cytoplasm contained numerous lipid droplets and abundant smooth endoplasmic reticulum (SER). Granular endoplasmic reticulum (GER) was less common. Mitochondria were most numerous from day 16 to day 44 of lactation and some of them contained large osmiophilic inclusions. Several types of granules and inclusions were present in the cytoplasm. During pregnancy, small dense-cored granules were common in P. nasuta and sparse in I. macrourus. They were still present in small numbers during early lactation in P. nasuta but were absent throughout lactation in I. macrourus. A special type of cell junction associated with endoplasmic reticulum was present between the luteal cells in P. nasuta but not in I. macrourus. The luteal cells of regressing CL on days 48, 50 and 53 of lactation were markedly reduced in size, with small irregularly shaped nuclei containing clumps of heterochromatin and indistinct nucleoli. The cells still contained numerous lipid droplets, and osmiophilic inclusions were still present in some of the mitochondria, which were reduced in number (and absent in the animal at day 50). Lancet-shaped spaces, which probably initially contained cholesterol crystals extracted by solvents during processing, were present in some of the regressing luteal cells. Organelles, including SER and GER, were either sparse or unrecognizable in luteal cells at advanced stages of regression. In general, the ultrastructural features of the luteal cells in fully formed and regressing CL of bandicoots were similar to those described in active and regressing CL of eutherian mammals.

scholarly journals Cholesterol and Steroid Synthesizing Smooth Endoplasmic Reticulum of Adrenocortical Cells Contains High Levels of Proteins Associated with the Translocation Channel

Endocrinology ◽  
2005 ◽  
Vol 146 (10) ◽  
pp. 4234-4249 ◽  
Author(s):  
Virginia H. Black ◽  
Archana Sanjay ◽  
Klaus van Leyen ◽  
Brett Lauring ◽  
Gert Kreibich
Keyword(s):  
Endoplasmic Reticulum ◽  
Rough Endoplasmic Reticulum ◽  
Smooth Endoplasmic Reticulum ◽  
Steroid Metabolism ◽  
Adrenocortical Cells ◽  
Steroid Synthesis ◽  
Local Synthesis ◽  
Peptide Cleavage ◽  
Cotranslational Translocation ◽  
Tubular Endoplasmic Reticulum

Steroid-secreting cells are characterized by abundant smooth endoplasmic reticulum whose membranes contain many enzymes involved in sterol and steroid synthesis. Yet they have relatively little morphologically identifiable rough endoplasmic reticulum, presumably required for synthesis and maintenance of the smooth membranes. In this study, we demonstrate that adrenal smooth microsomal subfractions enriched in smooth endoplasmic reticulum membranes contain high levels of translocation apparatus and oligosaccharyltransferase complex proteins, previously thought confined to rough endoplasmic reticulum. We further demonstrate that these smooth microsomal subfractions are capable of effecting cotranslational translocation, signal peptide cleavage, and N-glycosylation of newly synthesized polypeptides. This shifts the paradigm for distinction between smooth and rough endoplasmic reticulum. Confocal microscopy revealed the proteins to be distributed throughout the abundant tubular endoplasmic reticulum in these cells, which is predominantly smooth surfaced. We hypothesize that the broadly distributed translocon and oligosaccharyltransferase proteins participate in local synthesis and/or quality control of membrane proteins involved in cholesterol and steroid metabolism in a sterol-dependent and hormonally regulated manner.

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