Physiological and Pathological Regulation of Peripheral Metabolism by Gut-Peptide Hormones in Drosophila

Fine Structural Alterations in Thyroid Follicular Cells (FC) and Changes in Serum Thyroxine Produced by Feeding Polychlorinated Biphenyl (PCB) to Rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079929 ◽

1977 ◽

Vol 35 ◽

pp. 498-499

Author(s):

W.T. Collins ◽

Charles C. Capen ◽

Louis Kasza

Keyword(s):

Feed Efficiency ◽

Polychlorinated Biphenyl ◽

Serum Proteins ◽

Skin Lesions ◽

Hepatic Necrosis ◽

Ultrastructural Changes ◽

Lymphoid Tissues ◽

Heat Transfer Fluids ◽

Thyroid Follicular Cells ◽

Peripheral Metabolism

The widespread contamination of the environment with PCB, a compound used extensively by industry in hydraulic and heat transfer fluids as well as plasticizers and solvents in adhesives and sealants, has resulted in detectable tissue levels in a large portion of the human population, domestic animals, and wildlife. Intoxication with PCB produces severe hepatic necrosis, degeneration of lymphoid tissues and kidney, skin lesions, decreased reproductive performance, reduced feed efficiency, and decreased weight gain. PCB also has been reported to reduce the binding of thyroid hormone to serum proteins and enhance the peripheral metabolism of thyroxine with increased excretion of thyroxine-glucuronide in the bile (Bastomsky, Endocrinology 95: 1150-1155, 1974).The objectives of this investigation were (1) to investigate the histopathologic, histochemical, and ultrastructural changes in thyroid FC produced by the acute (4 week) and chronic (12 week) administration of low (50 ppm) and high (500 ppm) doses of PCB to rats, (2) to correlate these alterations to changes in serum immunoreactive thyroxine concentration, and (3) to investigate the persistence of the effects of PCB on the thyroid gland.

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Plant peptide hormone signalling

Essays in Biochemistry ◽

10.1042/bse0580115 ◽

2015 ◽

Vol 58 ◽

pp. 115-131 ◽

Cited By ~ 17

Author(s):

Ayane Motomitsu ◽

Shinichiro Sawa ◽

Takashi Ishida

Keyword(s):

Communication Systems ◽

Cell Communication ◽

Peptide Hormone ◽

Peptide Hormones ◽

Target Cells ◽

Signalling Molecules ◽

Receptor Complexes ◽

Environmental Responses ◽

Plant Life Cycle ◽

Multicellular Organisms

The ligand–receptor-based cell-to-cell communication system is one of the most important molecular bases for the establishment of complex multicellular organisms. Plants have evolved highly complex intercellular communication systems. Historical studies have identified several molecules, designated phytohormones, that function in these processes. Recent advances in molecular biological analyses have identified phytohormone receptors and signalling mediators, and have led to the discovery of numerous peptide-based signalling molecules. Subsequent analyses have revealed the involvement in and contribution of these peptides to multiple aspects of the plant life cycle, including development and environmental responses, similar to the functions of canonical phytohormones. On the basis of this knowledge, the view that these peptide hormones are pivotal regulators in plants is becoming increasingly accepted. Peptide hormones are transcribed from the genome and translated into peptides. However, these peptides generally undergo further post-translational modifications to enable them to exert their function. Peptide hormones are expressed in and secreted from specific cells or tissues. Apoplastic peptides are perceived by specialized receptors that are located at the surface of target cells. Peptide hormone–receptor complexes activate intracellular signalling through downstream molecules, including kinases and transcription factors, which then trigger cellular events. In this chapter we provide a comprehensive summary of the biological functions of peptide hormones, focusing on how they mature and the ways in which they modulate plant functions.

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Immunoglobulins G are precursors of peculiar peptide hormones

Immunology Letters ◽

10.1016/s0165-2478(97)88452-0 ◽

1997 ◽

Vol 56 (1-3) ◽

pp. 399

Author(s):

V Abramov

Keyword(s):

Peptide Hormones

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INHIBITION OF LIPOLYTIC ACTIVITY OF SYNTHETIC β1–24 AND β1–39 CORTICOTROPHIN BY ANTI-ACTH ANTISERUM

Acta Endocrinologica ◽

10.1530/acta.0.0510088 ◽

1966 ◽

Vol 51 (1) ◽

pp. 88-94 ◽

Cited By ~ 1

Author(s):

A. Villanueva ◽

S. J. H. Ashcroft ◽

J. P. Felber

Keyword(s):

Guinea Pig ◽

Lipolytic Activity ◽

Peptide Hormones ◽

Fat Pad ◽

Double Antibody ◽

Epididymal Fat ◽

Antibody Complex ◽

Radio Immunoassay ◽

Antigen Antibody

ABSTRACT The synthetic ACTH peptides β1–39 and β1–24 stimulated lipolysis as determined by the rat epididymal fat pad in vitro. The stimulating effect of these peptides was diminished by prior incubation of the peptides with antibodies produced by the guinea-pig against ACTH. The stimulating effect of these hormones was also diminished by the double antibody system used in the radio-immunoassay of ACTH and other peptide hormones, in which incubation with antiserum is followed by precipitation of the antigen-antibody complex by rabbit anti-guinea-pig-γ-globulin.

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METABOLISM AND MODE OF ACTION OF ANDROGENS IN TARGET TISSUES OF MALE RATS

Acta Endocrinologica ◽

10.1530/acta.0.0690165 ◽

1972 ◽

Vol 69 (1) ◽

pp. 165-173 ◽

Cited By ~ 9

Author(s):

H. Schmidt ◽

I. Noack ◽

K. D. Voigt

Keyword(s):

Cell Proliferation ◽

Cell Metabolism ◽

Seminal Vesicles ◽

Male Rats ◽

Ventral Prostate ◽

Nucleic Acid Content ◽

The Difference ◽

Independent Effects ◽

Sites Of Action ◽

Peripheral Metabolism

ABSTRACT The effect of testosterone and 5α-dihydrotestosterone on protein and nucleic acid content as well as on the activities of some enzymes has been studied in the ventral prostate and the seminal vesicles of immature castrated rats. Both androgens were given intraperitoneally in doses of 1 mg daily for one or three days the rats were sacrificed one day after the last injection. In the prostate it was found that 5α-dihydrotestosterone had a greater effect on DNA increase, i. e. cell proliferation than testosterone, whereas cell metabolism was stimulated by the two androgens to nearly the same extent. In the seminal vesicles a single dose led to the same results as had been obtained in the prostate, i. e. a greater cell proliferative action of 5α-dihydrotestosterone and an equal stimulation of cell metabolism by testosterone and 5α-dihydrotestosterone was also observed. When three doses of the two androgens were given, cell proliferation as well as cell metabolism in the seminal vesicles were significantly more increased after 5α-dihydrotestosterone than after testosterone. The difference of action after systemic administration of the two androgens is explained by their different accumulation and by their different peripheral metabolism in the target tissues. From the partly independent effects of various androgens on cell proliferation and cell metabolism the conclusion may be drawn that there exist at least two intracellular sites of action.

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