Ultrastructural Description of three Different Epithelial Cell Types in Rat Mammary Gland.

1976 ◽  
Vol 34 ◽  
pp. 146-147
Author(s):  
I.H. Russo ◽  
M. Ireland ◽  
W. Isenberg ◽  
J. Russo
Keyword(s):  
Mammary Gland ◽  
Virgin Female ◽  
Cell Types ◽  
Myoepithelial Cells ◽  
Uranyl Acetate ◽  
Female Rats ◽  
Sprague Dawley ◽  
Rat Mammary Gland ◽  
Intermediate Cells ◽  
Different Cell Types

The mammary gland is composed of epithelial and myoepithelial cells. In the present work, we show that the epithelial component is composed of three types of cells differing in their ultrastructural profiles.Sprague-Dawley virgin female rats, 60 to 100 days old, were sacrificed during estrus. The mammary gland was fixed in Karnovsky's fluid (1), embedded in Epon-Araldite (2), thin-sectioned, stained with uranyl acetate and lead citrate, and examined in an Hitachi HU-11A or a Siemens Elmiskop 1A. To see whether ultrastructural differences correspond to size differences, the nuclear and cytoplasmic areas of 1000 cells were determined from photographs at 10,000X, using a compensating polar planimeter.The population of epithelial cells in the mammary gland is comprised of three different cell types (Fig. 1): a) light cells, b) dark cells, and c) intermediate cells.

Ultrastructural Changes in the Mammary Epithelial Cell Population During Neoplastic Development Induced by A Chemical Carcinogen.

1976 ◽  
Vol 34 ◽  
pp. 250-251 ◽  
Author(s):  
J. Russo ◽  
W. Isenberg ◽  
M. Ireland ◽  
I.H. Russo
Keyword(s):  
Mammary Gland ◽  
Cell Population ◽  
Virgin Female ◽  
Histological Change ◽  
Mammary Epithelial ◽  
Female Rats ◽  
Ultrastructural Changes ◽  
Post Inoculation ◽  
Chemical Carcinogen ◽  
Sprague Dawley

The induction of rat mammary carcinoma by the chemical carcinogen DMBA is used as a model for the study of the human disease (1). We previously described the histochemical changes that occur in the mammary gland of DMBA treated animals before the earliest manifested histological change, the intraductal proliferation (IDP), was observed (2). In the present work, we demonstrate that a change in the stable cell population found in the resting mammary gland occurs after carcinogen administration.Fifty-five day old Sprague-Dawley virgin female rats were inoculated intragastrically with 20mg of 7,12-dimethylbenz(a)anthracene (DMBA) in 1ml sesame oil. Non-inoculated, age-matched females were used as controls. Mammary glands from control and inoculated rats were removed weekly from the time of inoculation until 60 days post-inoculation. For electron microscopy, the glands were immersed in Karnovsky's fixative, post-fixed in 1% OsO4, dehydrated, and embedded in an Epon-Araldite mixture. Thick (lμ) sections were stained with 1% toluidine blue and were used for selecting areas for ultrastructural study.

Basal Lamina Formation in DMBA Induced Mammary Carcinoma

1977 ◽  
Vol 35 ◽  
pp. 534-535
Author(s):  
I. Russo ◽  
J. Saby ◽  
J. Russo
Keyword(s):  
Mammary Carcinoma ◽  
Virgin Female ◽  
Mammary Glands ◽  
Sesame Oil ◽  
Female Rats ◽  
Ultrastructural Changes ◽  
Post Inoculation ◽  
Intermediate Type ◽  
Sprague Dawley ◽  
Intercellular Spaces

It has been previously demonstrated that DMBA-induced rat mammary carcinoma originates in the terminal end bud (TEB) of the mammary gland by proliferation of intermediate type cells (1). The earliest lesion identified is the intraductal proliferation (IDP), which gives rise to intraductal carcinomas. These evolve to cribriform, papillary and comedo types (2). In the present work, we report the ultrastructural changes that take place in the IDP for the formation of a cribriform pattern.Fifty-five-day-old Sprague Dawley virgin female rats were inoculated intra- gastrically with 20 mg 7,12-dimethylbenz(a)anthracene (DMBA) in 1 ml sesame oil. Non-inoculated, age-matched females were used as controls. Mammary glands from both control and experimental rats were removed weekly from the time of inoculation until 86 days post-inoculation. The glands were fixed and processed for electron microscopy (2).The first change observed in IDP's was the widening of intercellular spaces and the secretion of an electron dense material into these spaces (Fig. 1).

scholarly journals Enhanced synthesis of gelatinase and stromelysin by myoepithelial cells during involution of the rat mammary gland.

1992 ◽  
Vol 40 (5) ◽  
pp. 697-703 ◽  
Author(s):  
S R Dickson ◽  
M J Warburton
Keyword(s):  
Mammary Gland ◽  
Basement Membrane ◽  
Gelatin Zymography ◽  
Mammary Glands ◽  
Myoepithelial Cells ◽  
Immunofluorescence Staining ◽  
Rat Mammary Gland

During the involution of the mammary gland there is destruction of the basement membrane as the secretory alveolar structures degenerate. Immunofluorescence staining of sections of rat mammary gland with antibodies to 72 KD gelatinase (MMP-2) and stromelysin (MMP-3) revealed increased production of these two proteinases during involution. This increased expression was mostly restricted to myoepithelial cells. Increased expression during involution was also demonstrated by immunoblotting techniques. Gelatin zymography indicated that the predominant metalloproteinase present in involuting rat mammary glands was a 66 KD gelatinase.

Antiproliferative effect of dietary glucarate on the Sprague-Dawley rat mammary gland

1990 ◽  
Vol 49 (1) ◽  
pp. 51-57 ◽  
Author(s):  
Z. Walaszek ◽  
M. Hanausek ◽  
U. Sherman ◽  
A.K. Adams
Keyword(s):  
Mammary Gland ◽  
Antiproliferative Effect ◽  
Sprague Dawley ◽  
Sprague Dawley Rat ◽  
Rat Mammary Gland

scholarly journals Endogenous estrogen mediates vascular reactivity and distensibility in pregnant rat mesenteric arteries

2001 ◽  
Vol 280 (3) ◽  
pp. H956-H961 ◽  
Author(s):  
Yunlong Zhang ◽  
Ken G. Stewart ◽  
Sandra T. Davidge
Keyword(s):  
Vascular Reactivity ◽  
Pressor Response ◽  
Virgin Female ◽  
Mesenteric Arteries ◽  
Female Rats ◽  
Tamoxifen Treatment ◽  
Sprague Dawley ◽  
Arterial Distensibility ◽  
Pregnant Rat ◽  
Endogenous Estrogen

The role of estrogen in the maternal systemic cardiovascular adaptations during pregnancy is still controversial. Female Sprague-Dawley rats were implanted at day 14 of pregnancy with either a 50-mg tamoxifen pellet (estrogen receptor blocker, n = 10) or placebo pellet ( n = 10). Virgin female rats were a nonpregnant control ( n = 7). At days 20–22 of pregnancy, resistance-sized mesenteric arteries were mounted onto a dual-chamber arteriograph system. Pregnancy significantly blunted the pressor response to phenylephrine [measurement of the effective concentration that yielded 50% maximum response (EC50) values were 1.5 ± 0.22 vs. 0.69 ± 0.16 μM ( P < 0.05)] and enhanced vasodilation to ACh [EC50 = 1.13 ± 2.53 vs. 3.13 ± 6.04 nM ( P < 0.05)] compared with nonpregnant rats. However, tamoxifen treatment during pregnancy reversed these effects. Inhibition of nitric oxide (NO) synthase with N G-monomethyl-l-arginine (250 μM) shifted only the responses of the placebo-treated pregnant group to both phenylephrine and ACh. Arterial distensibility in the placebo-treated pregnant group was also significantly increased ( P < 0.05) compared with nonpregnant and tamoxifen-treated pregnant animals. In summary, endogenous estrogen during pregnancy increases NO-dependent modulation of vessel tone and arterial distensibility.

FINE STRUCTURE OF RAT PROLACTIN CELLS AFTER TREATMENT WITH A LONG ACTING DEPOT CONTRACEPTIVE

1978 ◽  
Vol 89 (2) ◽  
pp. 251-262 ◽  
Author(s):  
G. Aumüller ◽  
R. Wagner ◽  
K. J. Gräf
Keyword(s):  
Mammary Gland ◽  
Female Rats ◽  
Prolactin Cells ◽  
Stimulatory Action ◽  
Treatment Regimens ◽  
Morphological Findings ◽  
Oestradiol Benzoate ◽  
Rat Mammary Gland ◽  
Long Acting

ABSTRACT Adult intact female rats were injected with norethisterone oenanthate (NOe), with or without simultaneous administration of CB-154, or with oestradiol benzoate (OeB). The ultrastructure of prolactin (PRL) cells due to the various treatment regimens was investigated and compared with the situation found in controls. Both after treatment with NOe or NOe plus CB-154, the number of PRL cells increased and displayed various ultrastructure signs of stimulation. The determination of serum PRL levels coincides with these morphological findings. In all treated animals mammary gland DNA content was significantly increased. The results presented indicate that proliferative changes in the rat mammary gland depend predominantly on the presence of progestogenic activities additionally to PRL, whereas the effect of oestrogens was regarded as an indirect effect via their PRL-stimulatory action.

CYTOCHROME OXIDASE AND SUCCINIC OXIDASE ACTIVITY IN MAMMARY GLAND MITOCHONDRIA OF LACTATING RATS

1955 ◽  
Vol 33 (1) ◽  
pp. 904-908
Author(s):  
Jules Tuba ◽  
Patricia F. Orr ◽  
G. Stuart Wiberg
Keyword(s):  
Mammary Gland ◽  
Cytochrome Oxidase ◽  
Oxidase Activity ◽  
Succinic Dehydrogenase ◽  
Female Rats ◽  
Oxidative Enzymes ◽  
Mammary Tissue ◽  
Control Group ◽  
Succinic Dehydrogenase Activity ◽  
Rat Mammary Gland

The effect of lactation on some oxidative enzymes of rat mammary gland mitochondria was examined. Cytochrome oxidase levels were nearly doubled during lactation. Succinic oxidase activity was not demonstrable in breeder female rats four days after the cessation of nursing, or in a control group (non-lactating breeder females, which had weaned their young at least four weeks previously), but during the nursing period considerable activity of the enzyme was observed. Succinic dehydrogenase activity was negligible in mitochondria during involution of rat mammary tissue. On the other hand appreciable anaerobic glycolysis occurred in the resting gland. The greatly increased metabolic activity associated with lactation is reflected in the altered behavior of some of the enzymes of rat mammary gland mitochondria.

DIRECT ACTION OF TESTOSTERONE PROPIONATE ON THE RAT MAMMARY GLAND

1962 ◽  
Vol 40 (2) ◽  
pp. 265-276 ◽  
Author(s):  
K. Ahrén ◽  
L. Hamberger
Keyword(s):  
Mammary Gland ◽  
Testosterone Propionate ◽  
Direct Action ◽  
Local Effect ◽  
Hormonal Control ◽  
Female Rats ◽  
The Third ◽  
Alveolar Development ◽  
Male And Female Rats ◽  
Rat Mammary Gland

ABSTRACT Testosterone propionate in arachis oil was applied locally to the skin over the third left thoracic mammary gland (= experimental gland) of castrated male and female rats. Arachis oil was applied to the third right thoracic mammary gland (= control gland). After 21–23 days of local applications the development of the experimental and control glands was studied on whole mount preparations. It was found that small doses of testosterone (0.15 mg daily) stimulated slight but definite lobule-alveolar development in the experimental glands, while the control glands did not show any alveoli. Applications of higher doses of testosterone propionate (0.30 and 0.75 mg daily) stimulated extensive lobule-alveolar development in the experimental glands, while only few alveoli were produced in the control glands. It may therefore be concluded that the effect of testosterone on the rat mammary gland is not mediated through other endocrine glands, but is a direct, local effect on the mammary gland structures. The result is discussed in relation to our present knowledge of the hormonal control of different growth processes within the mammary glands.

scholarly journals The ultrastructural effects of excess maternal vitamin A on the primitive streak stage rat embryo

Development ◽  
1973 ◽  
Vol 30 (1) ◽  
pp. 219-242
Author(s):  
Gillian M. Morriss
Keyword(s):  
Vitamin A ◽  
Preliminary Investigation ◽  
Primitive Streak ◽  
Cell Types ◽  
Female Rats ◽  
Rat Embryo ◽  
Maternal Vitamin ◽  
Loss Of Contact ◽  
Migratory Movements ◽  
Different Cell Types

1. A single injection of 100000 i.u. vitamin A palmitate was administered to pregnant female rats on one of the days 0–14 of pregnancy. The litters were examined for malformations and prenatal death. On the basis of the results of this preliminary investigation, treatment on day 8 was selected for detailed study. 2. Day-8 embryos were examined with the electron microscope from 2 to 24 h after maternal vitamin A administration. Ultrastructural abnormalities were: membrane swelling (cytoplasmic vacuoles, ‘budding’, nuclear membrane irregularities, general swelling leading to cell death); changes in the extra- to intracellular fluid ratio; increase in the number of lipid droplets; autophagic vacuoles; condensed and swollen mitochondria. 3. These changes were not equally distributed among the different cell types. It is suggested that this differential effect leads to a loss of synchrony between the development of structures from the different germ layers, in addition to a general retardation. Loss of contact between mesoderm cells may delay normal migratory movements and induction of neural plate. The general retardation is related to the lower birthweights of treated embryos versus controls, and the differential effects to the subsequent abnormal morphogenesis.

Modeling of fibrocystic mastopathy in experiment on animals

2020 ◽  
Vol 28 (4) ◽  
pp. 429-436
Author(s):  
Svetlana A. Anisimova ◽  
Janna A. Svirina ◽  
Denis A. Maksaev
Keyword(s):  
Mammary Gland ◽  
Virgin Female ◽  
Mammary Glands ◽  
Female Rats ◽  
Fibrocystic Disease ◽  
Drug Induced ◽  
Fibrocystic Mastopathy ◽  
Hormonal Imbalance ◽  
Pathogenetic Factor ◽  
Almost All

Nowadays, hormonal imbalance is proven to be a factor that influences initiation of malignant and benign breast tumors. To study the aspects of participation of sex hormones in damage to organs and tissues, it may be necessary to model a common womens pathology fibrocystic disease of mammary glands characterized by the most pronounced effects of this pathogenetic factor, on experimental animals. Aim. To create a model of fibrocystic disease of mammary gland with the subsequent possibility of studying morphological manifestations of the disease in natural and drug-induced pathomorphism. Materials and Methods. The pathology was induced by intramuscular injection of 0.5 ml of 2% synestrol and 0.5 ml of 2.5% progesterone to virgin female rats on the 1st, 7th, 14th, 21st, 28th and 35th days of the experiment. For examination, histological preparations of inguinal mammary glands were made. The preparations were described and studied using morphometric analysis. Results. In the result of the experiment, pronounced macro- and microscopic alterations of mammary glands were found. Microscopic picture was similar to that observed in fibrocystic mastopathy in women. Almost all the morphometric parameters underwent reliable alterations in correspondence with the given pathology. Conclusion. A model of fibrocystic disease of mammary gland was obtained that may be used for further study of morphogenesis and methods of correction.

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