Action of Gastrointestinal Polypeptide Hormones on Pituitary Anterior Lobe Function

2015 ◽  
pp. 282-298
Author(s):  
Anna Ottlecz
Keyword(s):  
Anterior Lobe ◽  
Polypeptide Hormones

Secondary structure of polypeptide hormones of the anterior lobe of the pituitary gland

Biopolymers ◽  
1984 ◽  
Vol 23 (1) ◽  
pp. 5-22 ◽  
Author(s):  
A. A. Makarov ◽  
N. G. Esipova ◽  
V. M. Lobachov ◽  
B. A. Grishkovsky ◽  
Yu. A. Pankov
Keyword(s):  
Secondary Structure ◽  
Pituitary Gland ◽  
Anterior Lobe ◽  
Polypeptide Hormones

scholarly journals From Pituitary Stem Cell Differentiation to Regenerative Medicine

2021 ◽  
Vol 11 ◽  
Author(s):  
Maria Andrea Camilletti ◽  
Julian Martinez Mayer ◽  
Sebastian A. Vishnopolska ◽  
Maria Ines Perez-Millan
Keyword(s):  
Stem Cells ◽  
Stem Cell ◽  
Embryonic Stem ◽  
Stem Cell Differentiation ◽  
Cell Types ◽  
Anterior Lobe ◽  
Pituitary Hormone ◽  
Target Organs ◽  
Polypeptide Hormones ◽  
Induced Pluripotent

The anterior pituitary gland is comprised of specialized cell-types that produce and secrete polypeptide hormones in response to hypothalamic input and feedback from target organs. These specialized cells arise during embryonic development, from stem cells that express SOX2 and the pituitary transcription factor PROP1, which is necessary to establish the stem cell pool and promote an epithelial to mesenchymal-like transition, releasing progenitors from the niche. Human and mouse embryonic stem cells can differentiate into all major hormone-producing cell types of the anterior lobe in a highly plastic and dynamic manner. More recently human induced pluripotent stem cells (iPSCs) emerged as a viable alternative due to their plasticity and high proliferative capacity. This mini-review gives an overview of the major advances that have been achieved to develop protocols to generate pituitary hormone-producing cell types from stem cells and how these mechanisms are regulated. We also discuss their application in pituitary diseases, such as pituitary hormone deficiencies.

Fine Structural Changes in the Adenohypophyses of Rats Following Destruction of the Pituitary Stalk

1977 ◽  
Vol 35 ◽  
pp. 496-497
Author(s):  
K. Kovacs ◽  
E. Horvath ◽  
J. M. Bilbao ◽  
F. A. Laszlo ◽  
I. Domokos
Keyword(s):  
Structural Changes ◽  
Tissue Injury ◽  
Anterior Lobe ◽  
Uranyl Acetate ◽  
Male Rats ◽  
Pituitary Stalk ◽  
Sequence Of Events ◽  
Pituitary Glands ◽  
Electrolytic Lesions ◽  
Ultrathin Sections

Electrolytic lesions of the pituitary stalk in rats interrupt adenohypophysial blood flow and result in massive infarction of the anterior lobe. In order to obtain a deeper insight into the morphogenesis of tissue injury and to reveal the sequence of events, a fine structural investigation was undertaken on adenohypophyses of rats at various intervals following destruction of the pituitary stalk.The pituitary stalk was destroyed electrolytically, with a Horsley-Clarke apparatus on 27 male rats of the R-Amsterdam strain, weighing 180-200 g. Thirty minutes, 1,2,4,6 and 24 hours after surgery the animals were perfused with a glutaraldehyde-formalin solution. The skulls were then opened and the pituitary glands removed. The anterior lobes were fixed in glutaraldehyde-formalin solution, postfixed in osmium tetroxide and embedded in Durcupan. Ultrathin sections were stained with uranyl acetate and lead citrate and investigated with a Philips 300 electron microscope.

Two Distinct Types of Microfilaments in the Cytoplasm of Human Adenohypophysial Cells

1973 ◽  
Vol 31 ◽  
pp. 668-669
Author(s):  
E. Horvath ◽  
K. Kovacs ◽  
I. E. Stratmann ◽  
C. Ezrin
Keyword(s):  
Pituitary Tumors ◽  
Average Diameter ◽  
Anterior Lobe ◽  
Uranyl Acetate ◽  
Type I ◽  
Breast Cancer Patients ◽  
Human Pituitary ◽  
Severe Diabetes ◽  
Pituitary Glands ◽  
Membrane Bound

Surgically removed human pituitary glands as well as pituitary tumors fixed in glutaraldehyde, postfixed in osmium tetroxide, embedded in epon resin, stained with uranyl acetate and lead citrate have been investigated by electron microscopy in order to correlate ultrastructure with functional activity. In the course of this study two distinct types of microfilaments have been identified in the cytoplasm of adenohypophysiocytes.Type I microfilaments (Fig. 1) were found in the cytoplasm of anterior lobe cells of five female subjects with disseminated mammary cancer and two patients with severe diabetes mellitus. The breast cancer patients were treated pre-operatively for various periods of time with different doses of oxysteroids. The microfilaments had an average diameter of JO A, formed parallel bundles, were scattered irregularly in the cytoplasm and were frequently located in the perikaryon. They were not membrane-bound and failed to show any periodicity.

Ultrastructural investigation of an adenoma of the pituitary post mortem

1987 ◽  
Vol 45 ◽  
pp. 622-623
Author(s):  
Shirley Siew ◽  
W. C. deMendonca
Keyword(s):  
Deleterious Effect ◽  
Anterior Lobe ◽  
Definitive Diagnosis ◽  
Pars Intermedia ◽  
Post Mortem ◽  
Close Apposition ◽  
Autopsy Material ◽  
Progressive Loss ◽  
Transmission Electron ◽  
Means Of Transmission

The deleterious effect of post mortem degeneration results in a progressive loss of ultrastructural detail. This had led to reluctance (if not refusal) to examine autopsy material by means of transmission electron microscopy. Nevertheless, Johannesen has drawn attention to the fact that a sufficient amount of significant features may be preserved in order to enable the establishment of a definitive diagnosis, even on “graveyard” tissue.Routine histopathology of the autopsy organs of a woman of 78 showed the presence of a well circumscribed adenoma in the anterior lobe of the pituitary. The lesion came into close apposition to the pars intermedia. Its architecture was more compact and less vascular than that of the anterior lobe. However, there was some grouping of the cells in relation to blood vessels. The cells tended to be smaller, with a higher nucleocytoplasmic ratio. The cytoplasm showed a paucity of granules. In some of the cells, it was eosinophilic.

A COMPARISON BETWEEN THE EXOPHTHALMOS INHIBITING EFFECTS OF SODIUM-D- AND SODIUM-L-THYROXINE IN GUINEA PIGS

1962 ◽  
Vol 41 (4) ◽  
pp. 619-624 ◽  
Author(s):  
Björn Tengroth ◽  
Uno Zackrisson
Keyword(s):  
Hyaluronic Acid ◽  
Pituitary Gland ◽  
Guinea Pigs ◽  
Anterior Lobe ◽  
Optical Isomers ◽  
Connective Tissues ◽  
Response Curves ◽  
Experimental Animals ◽  
Inhibiting Effect ◽  
Caloric Effect

ABSTRACT The general change in the connective tissues which occurs in animals with experimentally produced exophthalmos, consists in an increase in the amount of hyaluronic acid, which binds the water in the connective tissue. Many regard this process as a stimulation of the mucinous system in the connective tissues, and consider this an explanation of the phenomenon of exophthalmos. When the experimental animals are injected with thyroxine or thyroid extract, the reaction observed is opposite to that seen following the injection of the anterior lobe of the pituitary gland. In the former case, there is a reduction in the amount of hyaluronic acid and consequently a decrease in the water content in the connective tissues. In the experiments in question, Na-d-thyroxine and Na-l-thyroxine), in crystalline form, were tested for their inhibiting effect on the development of exophthalmos in experimental animals. The animals used were male albino guinea-pigs. An extract of the anterior lobe of the pituitary gland (TSH Organon)) was used to produce exophthalmos. In previous work (Tengroth 1961), it was shown, using an X-ray measuring technique, that d-thyroxine, despite its poor caloric effect, like l-thyroxine had an exophthalmos-inhibiting effect. When comparing the dose-response curves of the exophthalmos-inhibiting properties of both these optical isomers, it appears that d-thyroxine has an inhibiting effect which is significantly greater than that of l-thyroxine. The significance of this observation is discussed.

ANALYSIS OF RADIOIMMUNOASSAY BY DISC ELECTROPHORESIS AND SUCROSE GRADIENT CENTRIFUGATION

1971 ◽  
Vol 66 (2) ◽  
pp. 257-265 ◽  
Author(s):  
Lubomir Valenta ◽  
Michel L. Aubert
Keyword(s):  
Sucrose Gradient ◽  
Solid Phase ◽  
Gradient Centrifugation ◽  
Human Growth ◽  
Disc Electrophoresis ◽  
Separate Analysis ◽  
Adrenocorticotrophic Hormone ◽  
Sucrose Gradient Centrifugation ◽  
Before And After ◽  
Polypeptide Hormones

ABSTRACT Radioiodine-labelled synthetic adrenocorticotrophic hormone (ACTH), human growth hormone (HGH), human chorionic somato-mammotrophin (HCS), and human (HTSH) and bovine (BTSH) thyroid stimulating hormones were studied by disc-electrophoresis and sucrose gradient centrifugation before and after incubation with corresponding antisera. All antisera contained 7 S antibodies. After incubation, soluble antigenantibody complexes besides a small amount of precipitate were observed in the incubation mixture, characteristic of each hormone. The complexes migrated like gamma globulins or more slowly on disc-electrophoresis. and on sucrose gradient centrifugation showed patterns dependent on the time of incubation. Light 7 or 9 S, or < 12 S complexes occurred mostly after incubation for several minutes (up to 30 min) before analysis. When incubation was prolonged to 24 h and more, these relatively light complexes disappeared or diminished in favour of heavier soluble or precipitating complexes. Reproducibly obtainable sedimentation patterns of the soluble complexes suggested some definite recombination of antigen molecules with 7 S antibodies. The complexes did not occur on incubation with other sera than an antiserum to a given hormone. They were not influenced by EDTA. Displacement of the radioactivity of the complexes into the free hormone peak was obtained by addition of a non-labelled hormone identical with the labelled one. Sucrose gradient centrifugation and disc-electrophoresis are recommended for the study of immunoreaction of diluted materials and for a separate analysis of different steps of the radioimmunoassay. Radioimmunoassay was introduced for the measurement of protein hormones by Yalow & Berson (1960). The method, described originally for insulin, was later adapted to the detection of a number of protein and polypeptide hormones. On incubation of the hormone with its antiserum, a soluble antigenantibody complex is formed, which is separated from an excess of the free hormone by various methods, e. g. chromatoelectrophoresis, precipitation with a second antibody, adsorption on a solid phase etc. (Hunter 1967). Sucrose gradient centrifugation and disc-electrophoresis were occasionally used to follow some isolated aspect of radioimmunoassay (Fitschen 1965; Monjardino et al. 1968). We are demonstrating that these methods made it possible to analyze the radioimmunoassay step by step and thus may be useful for practical purposes as well as in a study of the immunoreaction of diluted materials.

BEFUNDE AM GENITALTRAKTUS DER RATTE NACH CORTICOTROPIN-INJECTION UND IHRE DEUTUNG UNTER BERÜCKSICHTIGUNG DES ZELLBILDES DER ADENOHYPOPHYSE

1959 ◽  
Vol XXXII (II) ◽  
pp. 167-176 ◽  
Author(s):  
Walter Schätzle
Keyword(s):  
Adult Female ◽  
Single Injection ◽  
Anterior Lobe ◽  
Vaginal Epithelium ◽  
Female Rats ◽  
Normal Adult ◽  
List Type

ABSTRACT In normal adult female rats a single injection of 5 IU corticotrophin was followed by a retention of glucoproteid material in the anterior lobe of the hypophysis and by impairment of the luteinization. In spayed adult female rats the same corticotrophin administration caused stratification and mucification of the vaginal epithelium.

Impact of Prolactin Hipersecrey on Glucid and Lipid Metabolisms

2019 ◽  
Vol 70 (5) ◽  
pp. 1603-1607
Author(s):  
Elena Ionescu ◽  
Bogdan Virgil Cotoi ◽  
Anca Ganescu
Keyword(s):  
Cranial Nerves ◽  
Pituitary Tumors ◽  
Optic Chiasm ◽  
Anterior Lobe ◽  
Visual Field Defects ◽  
Large Tumor ◽  
Metabolic Complications ◽  
Clinical Onset ◽  
Vision Defects ◽  
Upper Level

Pituitary is a common terrain for the appearance of tumoral changes, representing the origin of about 15% of all intracranial tumors [13]. These tumors are, for the most part, histologically benign, as they arise from hormone secreting cells in the anterior lobe. Therefore, the aim of the paper is to specify the clinical and paraclinical clinical onset characteristics, the evolutionary peculiarities, as well as the metabolic complications secondary to the prolactin hypersecretion. The effects of prolactin-secreting pituitary tumors may occur as a result of mass effects of tumors or even hyperprolactinaemia. Because microadenomas are intrathecal, visual defects may not occur, but headaches occur more often (50%) than normal (27%) [1, 6]. A large tumor that extends beyond the limbs of the turkey can cause headaches and vision defects. The classical presentation is bitemporal hemianopsia due to the compression of the optic chiasm from a tumor that extends to the upper level. If chiasma is prefixed or if the tumor extends posteriorly, compression of a single optical system results in visual field defects similar. The lateral extension in the cavernous sinus can lead to the illness of the oculomotor function involving the cranial nerves III, IV and VI and the branches V1 and V2 of the cranial nerve V, alone or in combinations.

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