scholarly journals ELECTRON MICROSCOPIC STUDIES OF THE ANTERIOR PITUITARY GLAND

1953 ◽  
Vol 1 (2) ◽  
pp. 93-113 ◽  
Author(s):  
JAMES F. RINEHART ◽  
MARILYN G. FARQUHAR
Keyword(s):  
Golgi Apparatus ◽  
Anterior Pituitary ◽  
Secretory Activity ◽  
Anterior Lobe ◽  
Female Rats ◽  
Great Promise ◽  
Ground Substance ◽  
Normal Female ◽  
Electron Microscopic ◽  
Thin Sections

Technical methods for preparation of thin sections suitable for electron microscopy, while exacting, have been developed to a point of useful application. A series of electron micrographs from such sections of the anterior lobe of the pituitary glands of normal female rats are presented. It is evident that in many respects the nuclear and cytoplasmic detail revealed surpasses that which can be achieved by light microscopy and offers great promise for research in problems of cytophysiology and pathology. The various cell forms as seen in the normal anterior pituitary are illustrated, and tentative interpretations of functional states are made. Cytologic structures clearly demonstrated include `specific' granules, mitochondria, Golgi apparatus, cytoplasmic ground substance and cell membranes. Some acidophiles contain delicate intracellular canaliculi (or lamellae), and cytoplasmic vesicles and vacuoles are prominent in certain basophiles. These alterations, which are associated with enlargement of the Golgi apparatus, are believed to reflect secretory activity.

An Electron Microscopic Study of the Acute Effects of Hypothalamic Releasing Factors on the Anterior Pituitary Gland

1968 ◽  
Vol 26 ◽  
pp. 232-233
Author(s):  
P.W. Coates ◽  
E.A. Ashby ◽  
L. Krulich ◽  
A. Dhariwal ◽  
S. McCann
Keyword(s):  
Anterior Pituitary ◽  
Microscopic Investigation ◽  
Uranyl Acetate ◽  
Electron Microscopic Investigation ◽  
Electron Microscopic ◽  
Tissue Samples ◽  
Thin Sections ◽  
Dense Membrane ◽  
Membrane Bound ◽  
Releasing Factors

The morphologic effects on somatotrophs of crude sheep hypothalamic extract prepared from stalk-median eminence were studied by electron microscopy in conjunction with concurrently run bioassays performed on the same tissue samples taken from young adult male Sherman rats.Groups were divided into uninjected controls and injected experimentals sacrificed at 5', 15', and 30' after injection. Half of each anterior pituitary was prepared for electron microscopic investigation, the other half for bioassay. Fixation using collidine buffered osmium tetroxide was followed by dehydration and embedment in Maraglas. Uranyl acetate and lead citrate were used as stains. Thin sections were examined in a Philips EM 200.Somatotrophs from uninjected controls appeared as described in the literature (Fig. 1). In addition to other components, these cells contained moderate numbers of spherical, electron-dense, membrane-bound granules approximately 350 millicrons in diameter.

Purification of functional lactotrophs and somatotrophs from female rats using fluorescence-activated cell sorting

1990 ◽  
Vol 126 (2) ◽  
pp. 269-274 ◽  
Author(s):  
D. Wynick ◽  
R. Critchley ◽  
M. S. Venetikou ◽  
J. M. Burrin ◽  
S. R. Bloom
Keyword(s):  
Cell Surface ◽  
Cell Sorting ◽  
Anterior Pituitary ◽  
Cell Types ◽  
Female Rats ◽  
Normal Female ◽  
Pituitary Cells ◽  
Female Rat ◽  
Fluorescence Activated Cell Sorting ◽  
Surface Labelling

ABSTRACT As the secretory granules of anterior pituitary cells fuse with the cell surface, there would appear to be sufficient hormone present on the cell surface to be labelled by polyclonal hormone antibodies and thus analysed by flow cytometry. We have therefore applied fluorescence-activated cell sorting to these labelled pituitary cells. Percentage purity and depletion of other cell types was assessed by immunocytochemistry and the reverse haemolytic plaque assay (RHPA). Results demonstrate that fluorescence-activated cell sorting allows almost complete purification of functional lactotrophs and somatotrophs to 96·7 ±1·7 (s.e.m.)% and 98±1·0% respectively by immunocytochemistry, and to 95·8 ±1·1% and 97±0·8% respectively by RHPA. Depletion of other anterior pituitary cell types to less than 2% was demonstrated by both immunocytochemistry and RHPA. Fluorescence-activated cell sorting to this degree of purity was routinely possible with cell yields of 91 ±3·4%. To obtain such purity/depletion, it was necessary to use specific antisera of high titre, at concentrations which ensured maximal cell-surface labelling associated with maximal stimulation of hormonal secretion by the appropriate hypothalamic stimulatory factor. Separating cells on the basis of the intensity of prolactin cell-surface labelling demonstrated a low level of binding of the prolactin antibody to gonadotrophs (but not of sufficient fluorescence intensity to be sorted into the prolactin enriched population), raising the possibility of prolactin receptors on gonadotrophs. We were unable to demonstrate the presence of mammosomatotrophs in the normal female rat, since purified lactotrophs did not contain or secrete GH nor did purified somatotrophs contain or secrete prolactin. Journal of Endocrinology (1990) 126, 269–274

The Ultrastructural Basis For Increased Prolactin Synthesis and Release From Anterior Pituitary Glands of Estrogen-Progesterone Primed Ovariectomized Rats: Correlated Electron Microscopy and Radioimmunoassay

1973 ◽  
Vol 31 ◽  
pp. 564-565
Author(s):  
P. W. Coates ◽  
C. A. Blake ◽  
D. S. Maxwell ◽  
C. H. Sawyer
Keyword(s):  
Anterior Pituitary ◽  
Elevated Serum ◽  
Virgin Female ◽  
Estradiol Benzoate ◽  
Female Rats ◽  
Ovariectomized Rats ◽  
Serum Prolactin ◽  
Electron Microscopic ◽  
Pituitary Glands ◽  
Prolactin Synthesis

In rats, physiological studies show that ovariectomy results in a reduced concentration of circulating prolactin. Conversely, ovariectomized rats given estrogen have elevated serum prolactin and increased amounts of prolactin in the anterior pituitary gland. Separate electron microscopic studies suggest modifications in fine structure of prolactin producing (LTH) cells based on relatively large cumulative amounts of estrogen given alone or with comparably high doses of progesterone to adult virgin female or ovariectomized rats. This study was undertaken to provide a correlated morphological and physiological investigation of LTH cells and prolactin levels in a model commonly used by many researchers.Six to seven weeks after bilateral ovariectomy, a group of adult female rats was primed by a subcutaneous injection of 50 ng of estradiol benzoate and 25 mg of progesterone.

TROPHIC HORMONE CONTENT OF THE ANTERIOR LOBE OF THE PITUITARY GLAND IN NORMAL AND CASTRATE MALE DOGS

1960 ◽  
Vol XXXIV (II) ◽  
pp. 169-175 ◽  
Author(s):  
Julian M. Davidson ◽  
Alexander N. Contopoulos ◽  
William F. Ganong
Keyword(s):  
Pituitary Gland ◽  
Anterior Pituitary ◽  
Fold Increase ◽  
Response Characteristic ◽  
Anterior Lobe ◽  
Female Rats ◽  
Immature Female ◽  
Castrate Male ◽  
Effective Doses ◽  
Trophic Hormone

ABSTRACT Pituitary FSH, ICSH, and TSH activities of intact and castrate male dogs were assayed in hypophysectomized immature female rats by determining the minimum amount of anterior pituitary tissue necessary to produce a response characteristic of each of these hormones. In intact dogs only, pituitary ACTH and GH content were also determined. The minimum effective doses obtained for intact dogs in fractions of anterior pituitary were: FSH – 1.5, ICSH – 0.25, TSH – 0.016, ACTH – 0.025, GH – 0.125. Castration had no significant effect on TSH content, but resulted in a sixteen-fold increase in FSH content and a two-fold increase in ICSH content of the pituitary gland.

scholarly journals A COMPARISON OF ALCIAN BLUE-ALDEHYDE FUCHSIN AND PEROXIDASE-LABELED ANTIBODY STAINING TECHNIQUES IN THE RAT ADENOHYPOPHYSIS

1970 ◽  
Vol 18 (6) ◽  
pp. 450-454 ◽  
Author(s):  
ALICE E. SWOPE ◽  
RAYMOND H. KAHN ◽  
JAMES L. CONKLIN
Keyword(s):  
Alcian Blue ◽  
Anterior Pituitary ◽  
Anterior Lobe ◽  
Female Rats ◽  
Intermediate Lobe ◽  
Antibody Staining ◽  
Aldehyde Fuchsin ◽  
Tsh Cells ◽  
Staining Techniques ◽  
Lh Cells

The peroxidase-labeled antibody (P-Ab) technique was compared on adjacent sections with a permanganate-Alcian Blue (AB)-aldehyde fuchsin (AF) procedure on the anterior pituitary gland of young adult, female rats. The cells that stained with both AB and AF (AB, AF+) were large and polygonal and frequently possessed long processes; these cells correspond to those which reacted with the TSH antibody. The cells that stained only with AF reacted with the FSH antibody in the P-Ab technique and the cells which reacted with the LH antibody were not stained with either AB or AF.AB,AF+ cells ("TSH" cells) were distributed throughout the anterior lobe except along the lateral and dorsal peripheries of the gland and adjacent to the intermediate lobe, while both the AF+ ("FSH" cells) and the "LH" cells were distributed throughout the anterior lobe.

Massive liver enlargement accompanied by decreased drug metabolism. Effect of anterior pituitary extract on hepatic ultrastructure, zoxazolamine paralysis, and metabolism in the rat

1977 ◽  
Vol 55 (5) ◽  
pp. 1135-1142 ◽  
Author(s):  
S. Szabo ◽  
B. D. Garg ◽  
P. Kourounakis ◽  
B. Tuchweber
Keyword(s):  
Endoplasmic Reticulum ◽  
Drug Metabolism ◽  
Anterior Pituitary ◽  
Smooth Endoplasmic Reticulum ◽  
Electron Microscopic Examination ◽  
Liver Weight ◽  
Female Rats ◽  
Supernatant Fraction ◽  
Electron Microscopic ◽  
Liver Enlargement

The relationship between liver enlargement and drug metabolism was investigated in female rats. Hepatomegaly (e.g., 31% increase in liver weight in a 17-day experiment) was induced by injection of lyophylized anterior pituitary (LAP) extract The liver enlargement seemed to be due to an increase in the number and the size (enhanced water content and PAS-positive material) of hepatocytes. Electron microscopic examination of the liver revealed slight proliferation of the smooth endoplasmic reticulum and pronounced fragmentation and dilation of the rough endoplasmic reticulum. Zoxazolamine paralysis time was significantly prolonged (+55% and +102%) after 4 and 17 days, respectively, of treatment with LAP. Metabolism of zoxazolamine by the 9000 g supernatant fraction of the liver of rats given LAP for 17 days was reduced by 73%. Thus, the marked hepatomegaly induced by LAP was associated with a prolonged action of the drug which may result from a decrease in hepatic drug metabolism.

THE ADENOHYPOPHYSIS OF FEMALE RATS AFTER HYPOTHALAMIC OESTRADIOL IMPLANTS: AN ELECTRON MICROSCOPIC STUDY

1970 ◽  
Vol 47 (1) ◽  
pp. 101-110 ◽  
Author(s):  
D. ZAMBRANO ◽  
R. P. DEIS
Keyword(s):  
Microscopic Study ◽  
Adult Female ◽  
Median Eminence ◽  
Secretory Activity ◽  
Female Rats ◽  
Prolactin Cells ◽  
Electron Microscopic ◽  
Arcuate Nuclei ◽  
Periventricular Area ◽  
Ultrastructural Effect

SUMMARY The ultrastructural effect of oestradiol implants into the hypothalamus on the adenohypophysis of adult female rats was studied. The main results are the demonstration that mammotrophs or prolactin cells, and to a lesser extent somatotrophs, increased their secretory activity after bilateral implants into the median eminence and arcuate nuclei; in the periventricular area the reaction was weaker and in the anterior hypothalamus the response was negative. In animals with implants in the basal tuberal region, mammotrophs showed an asynchronous secretory activity. Mitosis has been found to occur in fully differentiated mammotrophs, a finding which can be correlated with the increased number of such cells after basal tuberal implants. The gonadotrophs appeared to be atrophied.

Increasing Access to Tomographic Resources: Web-based Telemicroscopy and Database

2001 ◽  
Vol 7 (S2) ◽  
pp. 92-93
Author(s):  
M. E. Martone ◽  
S. Peltier ◽  
S. Lamont ◽  
A. Gupta ◽  
B. Ludaescher ◽  
...  
Keyword(s):  
Golgi Apparatus ◽  
High Voltage ◽  
Cell Biology ◽  
Electron Tomography ◽  
The United States ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Electron Microscopes

The application of electron tomography to cell biology has led to important insights into the 3D fine structure of subcellular processes and organelles. Tomography has been particularly useful for studying relatively large, multi-component structures such as the Golgi apparatus, mitochondria and synaptic complexes. When combined with very powerful high voltage electron microscopes, tomography has also provided high resolution quantitative views of extended structures such as neuronal dendrites in very thick sections (4 μm) at electron microscopic resolution. The utility of tomography is twofold: first, it provides 3D examination of subcellular structure without the need for serial section analysis; second, because the computed slices through the tomographic volumes can be much thinner than is possible to produce by physical sectioning, it reveals structural detail in the range of 5-30 nm that tends to be obscured in conventional thin sections. Tomographic analysis has forced re-assessment of long-standing views of organelles such as mitochondria and the Golgi apparatus and as the technique advances, additional insights are likely forthcoming.Electron tomography is an expensive technique, both in terms of the instruments used and the computational resources required. The three major high voltage electron microscope resources in the United States, San Diego, Boulder and Albany, all are actively engaged in tomographic research and offer this important technology to the scientific community at large.

Comparative Histology of the Maculae Flavae of the Vocal Folds

2000 ◽  
Vol 109 (2) ◽  
pp. 136-140 ◽  
Author(s):  
Kiminori Sato ◽  
Minoru Hirano ◽  
Tadashi Nakashima
Keyword(s):  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Layered Structure ◽  
Vocal Folds ◽  
Comparative Investigation ◽  
Ground Substance ◽  
Electron Microscopic ◽  
Collagenous Fibers ◽  
Structure And Functions ◽  
Comparative Histology

A light and electron microscopic comparative investigation of the maculae flavae of the vocal folds was carried out on excised human and canine adult larynges. The structure and functions of human adult maculae flavae (HMF) were found to differ from those of canine adult maculae flavae (CMF). The maculae flavae were composed of fibroblasts, elastic and collagenous fibers, and ground substance in humans and canines. The density of fibroblasts in HMF was found to exceed that in CMF. Fibroblasts in HMF were stellate with processes or spindle-shaped, and the nucleus-cytoplasm (N/C) ratio was small. Rough endoplasmic reticulum and Golgi apparatus were well developed in the cytoplasm. Fibroblasts in CMF were oval, and the N/C ratio was large. Endoplasmic organs were poorly developed in the cytoplasm. Synthesized elastic and collagenous fibers were more numerous in HMF than CMF, and the density of both in HMF was much greater than that in CMF. Ground substance was more abundant in CMF than HMF. Apparently, CMF did not produce elastic and collagenous fibers in amounts sufficient to develop vocal ligaments. The HMF contributes to the formation of the vocal ligaments and the layered structure of human vocal folds.

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