Amyloid in the Corpora Amylacea of the Rat Mammary Gland

1978 ◽  
Vol 15 (3) ◽  
pp. 347-352 ◽  
Author(s):  
R. B. Beems ◽  
E. Gruys ◽  
B. J. Spit
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Mammary Gland ◽  
Amyloid Fibrils ◽  
Mammary Glands ◽  
Amyloid Deposition ◽  
Corpora Amylacea ◽  
Rat Mammary Gland

Histochemical and electron microscope studies indicated there was amyloid in corpora amylacea in tumors, duct ectasias and lobular hyperplasias of rat mammary glands. Electron microscopy showed fibrils that closely resembled amyloid fibrils in human and bovine amyloid and in bovine corpora amylacea. Amyloid deposition may be more common in rats than is generally thought.

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.

Mammary gland cell content during various phases of lactation

1962 ◽  
Vol 203 (5) ◽  
pp. 939-941 ◽  
Author(s):  
Richard C. Moon
Keyword(s):  
Mammary Gland ◽  
Deoxyribonucleic Acid ◽  
Cellular Proliferation ◽  
Gland Cell ◽  
Late Pregnancy ◽  
Mammary Glands ◽  
Lactation Period ◽  
Cell Content ◽  
Rat Mammary Gland ◽  
Mammary Gland Cell

Deoxyribonucleic acid (DNA) was used as an index of the cellular state of the rat mammary gland in late pregnancy ( day 20) and early ( day 1), intense ( day 14), and declining ( day 28) lactation. Dams sacrificed on day 28 of lactation were provided with foster litters on day 14 postpartum to insure a strong sucking stimulus during the lactation period from days 14–28. Mammary DNA increased 57% from day 20 of pregnancy to lactation day 14, but no significant change in DNA content was evident by day 1 of lactation. A significantly lower DNA concentration was observed in mammary glands of rats sacrificed at lactation day 28 when compared with that of animals killed at day 14 of lactation. The data suggest that cellular proliferation of mammary gland continues well into lactation and that a decline in lactation may be due, in part, to a reduction in the number of milk-secreting cells.

Needle-shaped amyloid deposition in rat mammary gland: evidence of a novel amyloid fibril protein

Amyloid ◽  
2019 ◽  
Vol 27 (1) ◽  
pp. 25-35 ◽  
Author(s):  
Tomoaki Murakami ◽  
Keiichi Noguchi ◽  
Naomi Hachiya ◽  
Fuyuki Kametani ◽  
Masayoshi Tasaki ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Amyloid Fibril ◽  
Amyloid Deposition ◽  
Rat Mammary Gland ◽  
Amyloid Fibril Protein

scholarly journals Prolactin receptor expression in the epithelia and stroma of the rat mammary gland

2001 ◽  
Vol 171 (1) ◽  
pp. 85-95 ◽  
Author(s):  
IG Camarillo ◽  
G Thordarson ◽  
JG Moffat ◽  
KM Van Horn ◽  
N Binart ◽  
...  
Keyword(s):  
Mammary Gland ◽  
Mammary Glands ◽  
Receptor Expression ◽  
Mrna Levels ◽  
Western Blots ◽  
Stromal Compartment ◽  
Mouse Tissues ◽  
Epithelial Compartment ◽  
Rat Mammary Gland ◽  
Mammary Tissues

The importance of prolactin (PRL) in regulating growth and differentiation of the mammary gland is well known. However, it is not well established whether PRL acts solely on the mammary epithelia or if it can also directly affect the mammary stroma. To determine where PRL could exert its effects within the mammary gland, we investigated the levels of expression and the localization of the PRL receptor (PRLR) in the epithelia and stroma of the rat mammary gland at different physiological stages. For these studies, we isolated parenchymal-free 'cleared' fat pads and intact mammary glands from virgin, 18-day-pregnant and 6-day-lactating rats. In addition, intact mammary tissues were enzymatically digested to obtain epithelial cells, free of stroma. The mammary tissues, intact gland, stroma and isolated epithelia, were then used for immunocytochemistry, protein extraction and isolation of total RNA. PRLR protein was detected in tissues using specific polyclonal antisera (PRLR-l) by immunocytochemistry and Western blot analysis. Messenger RNA for PRLR was measured by ribonuclease protection assay. Immunocytochemistry and Western blots with the PRLR-1 antisera detected PRLR in wild-type rat and mouse tissues, whereas the receptor protein was absent in tissues from PRLR gene-deficient mice. PRLR was found to be present both in the epithelia and stroma of mammary glands from virgin, pregnant and lactating rats, as determined by immunocytochemistry and Western blotting. Western blots revealed the predominance of three bands migrating at 88, 90 and 92 kDa in each of the rat mammary samples. These represent the long form of the PRLR. During pregnancy and lactation, PRLR protein increased in the epithelial compartment of the mammary gland but did not change within the stromal compartment at any physiological stage examined. We also found PRLR mRNA in both the epithelia and stroma of the mammary gland. Again, the stroma contained lower levels of PRLR mRNA compared with the epithelia at all physiological stages examined. Also, the PRLR mRNA levels within the stroma did not change significantly during pregnancy or lactation, whereas PRLR mRNA within the epithelia increased twofold during pregnancy and fourfold during lactation when compared with virgin rats. We conclude from this study that PRLR is expressed both in the stromal and epithelial compartment of the mammary gland. This finding suggests PRL may have a direct affect on the mammary stroma and by that route affect mammary gland development.

scholarly journals Pyruvate carboxylase in lactating rat and rabbit mammary gland

1969 ◽  
Vol 111 (3) ◽  
pp. 263-271 ◽  
Author(s):  
Bilquis Gul ◽  
R. Dils
Keyword(s):  
Mammary Gland ◽  
Pyruvate Carboxylase ◽  
Freeze Drying ◽  
Specific Activity ◽  
Subcellular Fractionation ◽  
Mammary Glands ◽  
Mitochondrial Fraction ◽  
Freezing And Thawing ◽  
Rat Mammary Gland ◽  
Assay Conditions

1. Pyruvate carboxylase [pyruvate–carbon dioxide ligase (ADP), EC 6.4.1.1] was found in cell-free preparations of lactating rat and rabbit mammary glands, and optimum assay conditions for this enzyme were determined. 2. Subcellular-fractionation studies with marker enzymes showed pyruvate carboxylase to be distributed between the mitochondrial and soluble fractions of lactating rat mammary gland. Evidence is presented that the soluble enzyme is not an artifact due to mitochondrial damage. 3. In contrast, pyruvate carboxylase in lactating rabbit mammary gland is confined to the mitochondrial fraction. 4. The final product of pyruvate carboxylase action in the mitochondrial and particle-free supernatant fractions of lactating rat mammary gland was shown to be citrate. 5. The effects of freeze-drying, ultrasonic treatment and freezing-and-thawing on the specific activity of mitochondrial pyruvate carboxylase were investigated.

RELATIONSHIP OF MITOSIS TO ALVEOLAR DEVELOPMENT IN THE RAT MAMMARY GLAND

1971 ◽  
Vol 50 (3) ◽  
pp. 501-505 ◽  
Author(s):  
W. G. DILLEY
Keyword(s):  
Mammary Gland ◽  
Mitotic Activity ◽  
Mammary Glands ◽  
Alveolar Development ◽  
Thymidine Labelling ◽  
Rat Mammary Gland ◽  
Relationship Of

SUMMARY After 3 and 5 days of culture of whole rat mammary glands in the presence of insulin, or insulin plus prolactin, or insulin plus prolactin plus aldosterone, or insulin plus prolactin plus oestradiol plus progesterone, there was good correlation between the levels of alveolar development and the [3H]thymidine labelling indices. Blockage of mitosis in explants developing in medium containing insulin plus prolactin also blocked alveolar development. Alveolar development is therefore proportional to and dependent on mitotic activity in the proper hormonal environment.

INFLUENCE OF THE ADRENAL CORTEX ON GROWTH PROCESSES IN THE RAT MAMMARY GLAND

1964 ◽  
Vol 30 (2) ◽  
pp. 171-179 ◽  
Author(s):  
L. HAMBERGER ◽  
K. AHRÉN
Keyword(s):  
Mammary Gland ◽  
Mammary Glands ◽  
Sprague Dawley ◽  
Growth Processes ◽  
Alveolar Development ◽  
Sprague Dawley Rats ◽  
Hypophysectomized Rats ◽  
Rat Mammary Gland ◽  
Adrenalectomized Rats

SUMMARY The role of adrenal cortical hormones in the response of the rat mammary gland to testosterone was studied in Sprague-Dawley rats. In gonadectomized rats with intact adrenals, local percutaneous application of testosterone stimulated lobulo-alveolar development in the mammary glands. This effect of testosterone was markedly reduced after adrenalectomy. Injections of cortisone into the adrenalectomized rats restored the mammary gland response to testosterone, whereas injections of oestrone did not. In adrenalectomized and hypophysectomized rats, injections of testosterone in combination with growth hormone produced a marked alveolar development in the mammary glands. The importance of gonadal, hypophysial and adrenocortical hormones for various growth processes in the mammary glands is discussed.

I131 accumulation by the lactating rat mammary gland

1963 ◽  
Vol 204 (5) ◽  
pp. 856-860 ◽  
Author(s):  
Clark E. Grosvenor
Keyword(s):  
Mammary Gland ◽  
Thyroid Gland ◽  
Trichloroacetic Acid ◽  
Milk Protein ◽  
Mammary Glands ◽  
Rat Mammary Gland

The mammary glands of lactating rats fed a low-iodine diet accumulated 50% of an injected I131 dose or five times as much as the thyroid gland and twice as much as excreted by the kidneys in 17–24 hr. Rats which accumulated greater amounts of I131 in their mammary glands had significantly lesser thyroidal I131 uptakes. KClO4 and methimazole significantly reduced accumulation of I131 in milk, KClO4 being the more potent. Methimazole acted primarily in reducing the binding of I131 to milk protein. The concentration of I131 in milk, trichloroacetic acid-precipitable I131 in milk and in plasma, and ratio of milk I131 to plasma I131 were significantly reduced by the addition of iodide to the diet. The amount of I131 in the milk was not correlated with the amount of milk secreted. Exogenous thyroxin inhibited thyroidal I131 uptake but did not influence accumulation of I131 by the mammary gland. Injection of thyrotrophin restored thyroidal uptake of I131 but did not affect accumulation of I131 by the mammary gland.

THE SECRETORY CAPACITY OF THE AUTOTRANSPLANTED HYPOPHYSIS AS INDICATED BY THE EFFECTS OF STEROID HORMONES ON THE MAMMARY GLANDS

1962 ◽  
Vol 39 (3) ◽  
pp. 338-354 ◽  
Author(s):  
Kurt Ahrén
Keyword(s):  
Growth Hormone ◽  
Mammary Gland ◽  
Pituitary Gland ◽  
Steroid Hormones ◽  
Testosterone Propionate ◽  
Mammary Glands ◽  
Kidney Capsule ◽  
Alveolar Development ◽  
Rat Mammary Gland ◽  
Secretory Capacity

ABSTRACT The capacity of the rat mammary gland to respond to testosterone stimulation with lobule-alveolar development only when growth hormone is present, has in these experiments been used as a method for studying whether the pituitary gland, autotransplanted into the kidney capsule, can secrete growth hormone. Injections of 0.05 or 0.25 mg of testosterone propionate daily for 14 days did not stimulate any lobule-alveolar development in the mammary glands of castrated rats with autotransplanted hypophysis. When this treatment was given for about 4 weeks, a few alveoli were seen in the mammary glands. In castrated rats with intact pituitary gland the same doses of testosterone propionate stimulated an extense lobule-alveolar development even after only 14 days of treatment. Injections of testosterone propionate together with growth hormone in rats with autotransplanted hypophysis stimulated the same degree of lobule-alveolar development as did injections of testosterone alone in rats with intact pituitary gland. These observations on the mammary glands indicate that there is a considerable deficiency of growth hormone in rats with the pituitary gland autotransplanted into the kidney capsule. These results are discussed, together with the value of the method used for estimating the presence of growth hormone.

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