Nutrient Transfer: Mammary Gland Regulation

1978 ◽

Vol 36 (2) ◽

pp. 46-47

Author(s):

Jan Zarzycki ◽

Joseph Szroeder

Keyword(s):

Mammary Gland ◽

Protein Denaturation ◽

Chemical Constituents ◽

Freeze Substitution ◽

Electron Microscopic Examination ◽

Mouse Mammary Gland ◽

Electron Microscopic ◽

Preparation Methods ◽

Microscopic Studies ◽

Ultrathin Frozen Sections

The mammary gland ultrastructure in various functional states is the object of our investigations. The material prepared for electron microscopic examination by the conventional chemical methods has several limitations, the most important are the protein denaturation processes and the loss of large amounts of chemical constituents from the cells. In relevance to this,one can't be sure about a degree the observed images are adequate to the realy ultrastructure of a living cell. To avoid the disadvantages of the chemical preparation methods,some autors worked out alternative physical methods based on tissue freezing / freeze-drying, freeze-substitution, freeze-eatching techniqs/; actually the technique of cryoultraraicrotomy,i,e.cutting ultrathin sections from deep frozen specimens is assented as a complete alternative method. According to the limitations of the routine plastic embbeding methods we were interested to analize the mammary gland ultrastructure during lactation by the cryoultramicrotomy method.

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The effect of bromocriptine on mammary-gland ultrastructure of hyperprolactinemic rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111136 ◽

1984 ◽

Vol 42 ◽

pp. 204-205

Author(s):

I.C. Murray

Keyword(s):

Mammary Gland ◽

Dopamine Agonist ◽

Alveolar Epithelium ◽

Mammary Glands ◽

Female Rats ◽

Control Group ◽

Cell Hyperplasia ◽

Once Daily ◽

Long Evans

In women, hyperprolactinemia is often due to a prolactin (PRL)-secreting adenoma or PRL cell hyperplasia. RRL excess stimulates the mammary glands and causes proliferation of the alveolar epithelium. Bromocriptine, a dopamine agonist, inhibits PRL secretion and is given to women to treat nonpuerperal galactorrhea. Old female rats have been reported to have PRL cell hyperplasia or adenoma leading to PRL hypersecretion and breast stimulation. Herein, we describe the effect of bromocriptine and consequently the reduction in serum PRL levels on the ultrastructure of rat mammary glands.Female Long-Evans rats, 23 months of age, were divided into control and bromocriptine-treated groups. The control animals were injected subcutaneously once daily with a 10% ethanol vehicle and were later divided into a normoprolactinemic control group with serum PRL levels under 30 ng/ml and a hyperprolactinemic control group with serum PRL levels above 30 ng/ml.

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

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100091238 ◽

1976 ◽

Vol 34 ◽

pp. 250-251 ◽

Cited By ~ 2

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.

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Anatomy and ultrastructure of haustoria in selected West Australian parasitic angiosperms

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010016100x ◽

1990 ◽

Vol 48 (3) ◽

pp. 690-691

Author(s):

John Kuo ◽

John S. Pate

Keyword(s):

Parasitic Plants ◽

The Other ◽

Nutrient Transfer ◽

Direct Solution ◽

Tracheary Elements ◽

Solute Transfer ◽

Glycol Methacrylate ◽

Australian Species ◽

Anatomy And Ultrastructure ◽

Solution Transfer

Our understanding of nutrient transfer between host and flowering parasitic plants is usually based mainly on physiological concepts, with little information on haustorial structure related to function. The aim of this paper is to study the haustorial interface and possible pathways of water and solute transfer between a number of host and parasites.Haustorial tissues were fixed in glutaraldehyde and embedded in glycol methacrylate (LM), or fixed in glutaraldehyde then OsO4 and embedded in Spurr’s resin (TEM).Our study shows that lumen to lumen continuity occurs between tracheary elements of a host and four S.W. Australian species of aerial mistletoes (Fig. 1), and some root hemiparasites (Exocarpos spp. and Anthobolus foveolatus) (Fig. 2). On the other hand, haustorial interfaces of the root hemiparasites Olax phyllanthi and Santalum (2 species) are comprised mainly of parenchyma, as opposed to terminating tracheads or vessels, implying that direct solution transfer between partners via vessels or tracheary elements may be limited (Fig. 3).

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