Sexual differentiation of the urogenital tract in the chicken embryo: autoradiographic localization of sex-steroid target cells during development

The determinant role ascribed to steroid hormones in sexual differentiation of the reproductive tract of the embryo implies the presence of target cells for sex steroids. An autoradiographic technique adapted for diffusible compounds was employed to characterize and localize cells which concentrate either [3H]oestradiol (E2) or [3H]dihydrotestosterone (DHT) in their nuclei. This paper describes the topographical distribution of cells containing receptor sites for oestrogen or androgen in various tissues of the reproductive tract of chicken embryos from day 6 to 15 of incubation. Receptor sites for oestradiol are present in the mesenchyme of the cloaca and in urodeum and vascular body. In the lower part of the Wolffian duct, only epithelial cells display nuclear labelling. In the Müllerian duct, nuclear receptor sites for [3H]oestradiol are observed not before day 15. Receptor sites for DHT are localized in the mesenchyme of the cloacal region from day 7 to 15. The Wolffian, but not the Müllerian duct contains receptor sites for DHT in the nuclei of epithelial and mesenchymal cells. Cross-competition experiments between [3H]E2 or [3H]DHT and unlabelled DHT or E2 respectively, show that 2 different types of receptor sites exist. The observations indicate: (a) complementary roles for oestrogenic and androgenic hormones in embryonic sexual differentiation; (b) precocity of receptors for sex hormones during embryonic development; (c) importance of mesenchyme in differentiation processes which are sex-steroid dependent.

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The bursa of Fabricius of the chicken embryo: localization and ontogenic evolution of sex-steroid target cells

Development ◽

10.1242/dev.63.1.225 ◽

1981 ◽

Vol 63 (1) ◽

pp. 225-231

Author(s):

Jean-Marie Gasc ◽

Walter E. Stumpf

Keyword(s):

Chick Embryo ◽

Steroid Hormones ◽

Normal Development ◽

Bursa Of Fabricius ◽

Sex Steroid ◽

Target Cells ◽

Immune Organ ◽

Receptor Sites ◽

High Doses ◽

Autoradiographic Technique

Androgenic hormones induce inhibition or regression of the bursa of Fabricius in the chick embryo. The high doses of hormones necessary to this involution raises the question of the processes involved and their putative role in the normal development of the bursa. If androgens play a role it is mediated by receptor sites in target cells. Using an autoradiographic technique, receptor sites for androgenic hormones were localized in mesenchymal cells of the bursa from the primordium (7-day embryo) up to the fully differentiated immune organ (15-day embryo). No target cells containing receptor sites in their nuclei were observed in the endodermic epithelium or the follicles. Oestrogen target cells in very small number are found in the mesenchyme of the bursa, in 15-day embryos. The early presence of receptor sites for steroid hormones in the bursa of Fabricius shows that the normal development may be influenced by androgens, but the actual effects are yet to be demonstrated.

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Autoradiographic Studies of Steroid Receptor Sites in Embryonic Tissues,

Journal of Histochemistry & Cytochemistry ◽

10.1177/29.1a_suppl.7288153 ◽

1981 ◽

Vol 29 (1A_suppl) ◽

pp. 181-189 ◽

Cited By ~ 4

Author(s):

Jean-Marie Gasc

Keyword(s):

Steroid Hormones ◽

Sex Steroids ◽

Anterior Pituitary ◽

Reproductive Tract ◽

Steroid Receptor ◽

Bursa Of Fabricius ◽

Target Cells ◽

Embryonic Tissues ◽

Receptor Sites ◽

Autoradiographic Technique

An autoradiographic technique adapted to diffusible compounds was used to localize steroid receptor sites in various tissues of the chicken embryo. In this article are presented results obtained on the gonads, the reproductive tract, the bursa of Fabricius, and the anterior pituitary after injection of either 3H-estradiol or 3H-dihydrotes-tosterone into 5 1/2- to 15-day-old chicken embryos. Target cells for steroid hormones, either estrogen or androgen, or both, are present in these organs early in the development. The precocity of the receptors suggests that sex steroids may influence embryonic differentiation earlier than currently recognized. The presence of the receptors in a variety of organs or tissues, known or unsuspected target for steroids, emphasizes the very diversified roles of sex steroid hormones in the differentiation processes. Conditions for these receptors to be active are discussed with respect to particularities of the embryonic system.

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Estrogen target cells in gonads of the chicken embryo during sexual differentiation

Development ◽

10.1242/dev.55.1.331 ◽

1980 ◽

Vol 55 (1) ◽

pp. 331-342

Author(s):

Jean-Marie Gasc

Keyword(s):

Steroid Hormones ◽

Sexual Differentiation ◽

Binding Sites ◽

Chicken Embryo ◽

Physiological Role ◽

Germinal Epithelium ◽

Target Cells ◽

Nuclear Labelling ◽

The Right ◽

Sites Of Action

Estrogen target cells were searched for in the differentiating gonads of the chicken embryo in order (1) to establish at the cellular level that steroid hormones can play a physiological role in gonadal sexual differentiation, and (2) to localize their sites of action. An autoradiographic technique carried out with frozen sections was employed to demonstrate the presence of binding sites for radiolabelled hormone in the nuclei of the target cells. Target cells for [3H]estradiol are found similarly in gonads of both male and female embryos from 5½ (stage 27 of H and H) to 7 days of incubation. Estrogen target cells are observed in the germinal epithelium of the left but not the right gonad, and in the medulla of both the right and left gonads. In the medulla, numerous cells inside the cords are a target for estradiol. The germ cells, difficult to identify unmistakably in the experimental conditions, do not seem to be a target for estrogen hormones. A 100-fold excess of unlabelled estradiol abolishes the nuclear labelling, which is only slightly reduced after a similar excess of unlabelled dihydrotestosterone. It is concluded that the nuclear binding sites have a limited capacity for steroid hormones and are specific for estrogen hormones. The lack of clear and consistent nuclear labelling after [3H]dihydrotestosterone injection confirms the specificity of the [3H]estradiol nuclear labelling. At day 10 of incubation, only the undifferentiated remnant of the germinal epithelium in the left testis still displays labelled cells after [3H]estradiol injection. These observations confirm the determinative role currently ascribed to the estrogen hormones in the cortical differentiation, but they also emphasize that this role extends to the medulla of both gonads. In light of this presence of estrogen receptor sites in the medullary cords as well as in the germinal epithelium, one can assign the estrogen hormones more specific and diversified roles than currently believed. These roles also appear very precocious in the process of gonadal differentiation. Finally, the absence of target cells for estrogen hormones in the germinal epithelium of the right gonad accounts for the lack of cortical differentiation on the right side.

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SPERM PREFERENCE IN DROSOPHILA MELANOGASTER †

Genetics ◽

10.1093/genetics/71.3.417 ◽

1972 ◽

Vol 71 (3) ◽

pp. 417-427

Author(s):

D Childress ◽

D L Hartl

Keyword(s):

Drosophila Melanogaster ◽

Reproductive Tract ◽

Meiotic Drive ◽

Prior Exposure ◽

Different Types

Abstract A mating is described in which the females appear actively to discriminate against one of the genotypes of sperm. The males in the mating carry T(1;4)B S , and the sperm type selected against is the B S+4-bearing segregant. Prior exposure of the reproductive tract of the females to B S+4-bearing sperm seems to enhance the ability of the females to subsequently discriminate against B S+4-bearing sperm. Thus it appears that at least some females of Drosophila melanogaster do possess a mechanism whereby different types of sperm can be distinguished—the sperm preference observed in this system appears to be independent of the meiotic drive in the T(1;4)B S males.

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Extracellular cytolysis by activated macrophages and granulocytes. I. Pharmacologic triggering of effector cells and the release of hydrogen peroxide.

Journal of Experimental Medicine ◽

10.1084/jem.149.1.84 ◽

1979 ◽

Vol 149 (1) ◽

pp. 84-99 ◽

Cited By ~ 250

Author(s):

C F Nathan ◽

L H Brukner ◽

S C Silverstein ◽

Z A Cohn

Keyword(s):

Trypan Blue ◽

Response Curve ◽

Target Cells ◽

Activated Macrophages ◽

Lymphoma Cells ◽

Effector Cells ◽

Proteose Peptone ◽

Standard Assay ◽

Different Types ◽

J774 Cells

Lymphoma cells were rapidly lysed by activated macrophages and granulocytes in the presence of PMA. Release of 51Cr from lymphoma cells correlated closely with their destruction as viewed by scanning electron microscopy, and with reduction in the number of trypan blue-excluding cells. The standard assay involved 51 Cr release measured at 4.5 h, but injury appeared to be complete in 1 h. Of eight different types of effector cells tested, only those releasing abundant H2O2 in response to PMA were effective, that, is BCG-, C. parvum-, or casein-activated macrophages, or thioglycollate-elicited granulocytes. Normal macrophages, J774 cells, or macrophages elicited with thioglycollate broth or proteose-peptone were ineffective. BCG-activated macrophages and granulocytes caused 50% specific release of 51Cr from P388 lymphoma cells at E:T ratios between 1.4 and 4.5, and from mouse erythrocytes at E:T ratios of 0.017 to 0.025. 10 types of target cells varied widely in their susceptibility to lysis by reagent H2O2, with one-half maximal lysis occurring at H2O2 concentrations ranging from 3.63 X 10(-6) M to 3.85 X 10(-5) M. Effector cells were expected to generate approximately that much H2O2 during the period of injury. Susceptibility of the target cells to lysis by PMA-triggered granulocytes correlated closely with their sensitivity to H2O2 (r = 0.98). The membrane-active agents LPS and digitonin, which did not trigger H2O2 release, did not trigger cytotoxicity. The dose-response curve for triggering of H2O2 release by PMA was identical to that for triggering cytotoxicity. These results provided strong circumstantial evidence for the importance of H2O2 in extracellular cytolysis by activated macrophages and granulocytes when pharmacologically triggered.

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Altered sexual differentiation of hepatic uridine diphosphate glucuronyltransferase by neonatal hormone treatment in rats

Biochemical Journal ◽

10.1042/bj1800313 ◽

1979 ◽

Vol 180 (2) ◽

pp. 313-318 ◽

Cited By ~ 30

Author(s):

Coral A. Lamartiniere ◽

Cindy S. Dieringer ◽

Etsuko Kita ◽

George W. Lucier

Keyword(s):

Enzyme Activity ◽

Adult Male ◽

Sexual Differentiation ◽

Reproductive Tract ◽

Testosterone Propionate ◽

Hormone Treatment ◽

Male Rats ◽

Ventral Prostate ◽

Uridine Diphosphate ◽

Neonatal Administration

The hepatic microsomal enzyme UDP-glucuronyltransferase undergoes a complex developmental pattern in which enzyme activity is first detectable on the 18th day of gestation in rats. Prepubertal activities are similar for males and females. However, postpubertal sexual differentiation of enzyme activity occurs in which male activities are twice those of females. Neonatal administration of testosterone propionate or diethylstilboestrol to intact animals resulted in lowered UDP-glucuronyltransferase activity in liver microsomal fractions of adult male rats, whereas no changes were observed in the adult females and prepubertal male and female animals. Neonatal administration of testosterone propionate and diethylstilboestrol adversely affected male reproductive-tract development as evidenced by decreased weights of testes, seminal vesicles and ventral prostate. Diethylstilboestrol also markedly decreased spermatogenesis. Hypophysectomy of adult male rats resulted in negative modulation of microsomal UDP-glucuronyltransferase and prevented the sexual differentiation of enzyme activity. In contrast hypophysectomy had no effect on female UDP-glucuronyltransferase activity. A pituitary transplant under the kidney capsule was not capable of reversing the enzyme effects of hypophysectomy, therefore suggesting that the male pituitary factor(s) responsible for positive modulation of UDP-glucuronyltransferase might be under hypothalamic control in the form of a releasing factor. Neonatal testosterone propionate and diethylstilboestrol administration apparently interfered with the normal sequence of postpubertal UDP-glucuronyltransferase sexual differentiation.

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The mechanism of T cell mediated cytotoxicity IV. Studies on communicating junctions between cells in contact

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1977.0030 ◽

1977 ◽

Vol 196 (1122) ◽

pp. 73-84 ◽

Cited By ~ 11

Keyword(s):

T Cell ◽

Mammalian Cells ◽

Cytotoxic T Cells ◽

Diploid Cell ◽

Target Cells ◽

Cytotoxic Lymphocytes ◽

Communicating Junctions ◽

Unique System ◽

Pass Through ◽

Autoradiographic Technique

A modified autoradiographic technique has been developed which makes it possible to demonstrate the intercellular transfer of diffusible molecules through communicating junctions. This technique has been used to decide whether or not there is a cytoplasmic union between cytotoxic lymphocytes and the target cells they destroy. The transfer of 51 Cr, [ 3 H]uridine and [ 3 H]choline has been demonstrated between human diploid cell line cells (MRC 5) in contact. This has provided a system in which the techniques could be assessed. The demonstration that 51 Cr can pass through communicating junctions provides a unique system for the investigations of these structures. Despite the fact that all three labels could transfer between MRC 5 cells in contact, no transfer between cytotoxic T cells and P815 target cells could be demonstrated during a cytotoxic reaction. The reported transfer of fluorescein can probably be attributed to the transfer of fluorescein ester via the extracellular space. It is concluded, therefore, that communicating junctions of the type that can form between certain mammalian cells in contact do not contribute to the mechanism of T cell cytotoxicity.

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Simultaneous Exposure of Different Nanoparticles Influences Cell Uptake

Pharmaceutics ◽

10.3390/pharmaceutics14010136 ◽

2022 ◽

Vol 14 (1) ◽

pp. 136

Author(s):

Isa de Boer ◽

Ceri J. Richards ◽

Christoffer Åberg

Keyword(s):

Drug Delivery ◽

Individual Cell ◽

Model System ◽

Cell Uptake ◽

Target Cells ◽

Cell Level ◽

Polystyrene Nanoparticles ◽

Simultaneous Exposure ◽

Different Types ◽

Uptake Studies

Drug delivery using nano-sized carriers holds tremendous potential for curing a range of diseases. The internalisation of nanoparticles by cells, however, remains poorly understood, restricting the possibility for optimising entrance into target cells, avoiding off-target cells and evading clearance. The majority of nanoparticle cell uptake studies have been performed in the presence of only the particle of interest; here, we instead report measurements of uptake when the cells are exposed to two different types of nanoparticles at the same time. We used carboxylated polystyrene nanoparticles of two different sizes as a model system and exposed them to HeLa cells in the presence of a biomolecular corona. Using flow cytometry, we quantify the uptake at both average and individual cell level. Consistent with previous literature, we show that uptake of the larger particles is impeded in the presence of competing smaller particles and, conversely, that uptake of the smaller particles is promoted by competing larger particles. While the mechanism(s) underlying these observations remain(s) undetermined, we are partly able to restrain the likely possibilities. In the future, these effects could conceivably be used to enhance uptake of nano-sized particles used for drug delivery, by administering two different types of particles at the same time.

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