Pituitary hormones in teleost fish with emphasis on gonadotropins
Thesis (Ph.D.)--Memorial University of Newfoundland, 1980. Biochemistry Bibliography: leaves 165-179. This investigation on fish gonadotropins provides considerable evidence to support the concept of duality of gonadotropins in teleosts proposed by Campbell and Idler in 1976. Vitellogenic hormones w...
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ftmemorialunivdc:oai:collections.mun.ca:theses2/215384 2023-05-15T17:23:31+02:00 Pituitary hormones in teleost fish with emphasis on gonadotropins Ng, Tzi Bun, 1951- Memorial University of Newfoundland. Dept. of Biochemistry 1979 xvii, 182 leaves : ill. Image/jpeg; Application/pdf http://collections.mun.ca/cdm/ref/collection/theses2/id/215384 Eng eng Electronic Theses and Dissertations (34.80 MB) -- http://collections.mun.ca/PDFs/theses/Ng_TziBun.pdf 75062059 http://collections.mun.ca/cdm/ref/collection/theses2/id/215384 The author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission. Paper copy kept in the Centre for Newfoundland Studies, Memorial University Libraries Pituitary hormones Gonadotropin Text Electronic thesis or dissertation 1979 ftmemorialunivdc 2015-08-06T19:17:26Z Thesis (Ph.D.)--Memorial University of Newfoundland, 1980. Biochemistry Bibliography: leaves 165-179. This investigation on fish gonadotropins provides considerable evidence to support the concept of duality of gonadotropins in teleosts proposed by Campbell and Idler in 1976. Vitellogenic hormones were isolated from pituitaries of American plaice (Hippoglossoides platessoides) and winter flounder (PseudopTeuronectes americanus) and chum salmon (Oncorhynchus keta), devoid of oocyte maturational and androgenic activities, and they could be distinguished from the maturational hormones which were active in stimulating oocyte maturation and androgen production. The bioassays used to isolate the vitellogenic and maturational hormones utilized the hypophysectomized flounder as the assay animal, and this study represents one of the few investigations utilizing homologous bioassays to isolate fish gonadotropins. -- Vitellogenic and maturational hormones are different in their amino acid compositions, carbohydrate contents, immunological activities and chromatographic behavior on Concanavalin A-Sepharose. An antiserum to vitellogenic hormone was capable of inhibiting incorporation of vitellogenin into the ovary, whereas an antiserum to maturational hormone depressed the plasma concentrations of estradiol and vitellogenin, indicating that the two gonadotropins play different roles in fish reproduction. Chromatography of maturational hormone on Concanavalin A-Sepharose did not lead to isolation of additional material unadsorbed on the immobilized lectin. All available evidence thus suggest that the vitellogenic hormone and the maturational hormone are different entities. -- Thyroid stimulating hormone and gonadotropin were shown to be separate hormones. Two thyroid stimulating hormones could be isolated from pituitaries of both American plaice and winter flounder. The thyroid stimulating hormone unadsorbed on Concanavalin A-Sepharose stimulated mainly the production of triiodothyronine in hypophysectomized flounder while the thyroid stimulating hormone adsorbed on the immobilized lectin enhanced mainly the production of thyroxine. Thesis Newfoundland studies University of Newfoundland Memorial University of Newfoundland: Digital Archives Initiative (DAI) Keta ENVELOPE(-19.455,-19.455,65.656,65.656) |
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Memorial University of Newfoundland: Digital Archives Initiative (DAI) |
op_collection_id |
ftmemorialunivdc |
language |
English |
topic |
Pituitary hormones Gonadotropin |
spellingShingle |
Pituitary hormones Gonadotropin Ng, Tzi Bun, 1951- Pituitary hormones in teleost fish with emphasis on gonadotropins |
topic_facet |
Pituitary hormones Gonadotropin |
description |
Thesis (Ph.D.)--Memorial University of Newfoundland, 1980. Biochemistry Bibliography: leaves 165-179. This investigation on fish gonadotropins provides considerable evidence to support the concept of duality of gonadotropins in teleosts proposed by Campbell and Idler in 1976. Vitellogenic hormones were isolated from pituitaries of American plaice (Hippoglossoides platessoides) and winter flounder (PseudopTeuronectes americanus) and chum salmon (Oncorhynchus keta), devoid of oocyte maturational and androgenic activities, and they could be distinguished from the maturational hormones which were active in stimulating oocyte maturation and androgen production. The bioassays used to isolate the vitellogenic and maturational hormones utilized the hypophysectomized flounder as the assay animal, and this study represents one of the few investigations utilizing homologous bioassays to isolate fish gonadotropins. -- Vitellogenic and maturational hormones are different in their amino acid compositions, carbohydrate contents, immunological activities and chromatographic behavior on Concanavalin A-Sepharose. An antiserum to vitellogenic hormone was capable of inhibiting incorporation of vitellogenin into the ovary, whereas an antiserum to maturational hormone depressed the plasma concentrations of estradiol and vitellogenin, indicating that the two gonadotropins play different roles in fish reproduction. Chromatography of maturational hormone on Concanavalin A-Sepharose did not lead to isolation of additional material unadsorbed on the immobilized lectin. All available evidence thus suggest that the vitellogenic hormone and the maturational hormone are different entities. -- Thyroid stimulating hormone and gonadotropin were shown to be separate hormones. Two thyroid stimulating hormones could be isolated from pituitaries of both American plaice and winter flounder. The thyroid stimulating hormone unadsorbed on Concanavalin A-Sepharose stimulated mainly the production of triiodothyronine in hypophysectomized flounder while the thyroid stimulating hormone adsorbed on the immobilized lectin enhanced mainly the production of thyroxine. |
author2 |
Memorial University of Newfoundland. Dept. of Biochemistry |
format |
Thesis |
author |
Ng, Tzi Bun, 1951- |
author_facet |
Ng, Tzi Bun, 1951- |
author_sort |
Ng, Tzi Bun, 1951- |
title |
Pituitary hormones in teleost fish with emphasis on gonadotropins |
title_short |
Pituitary hormones in teleost fish with emphasis on gonadotropins |
title_full |
Pituitary hormones in teleost fish with emphasis on gonadotropins |
title_fullStr |
Pituitary hormones in teleost fish with emphasis on gonadotropins |
title_full_unstemmed |
Pituitary hormones in teleost fish with emphasis on gonadotropins |
title_sort |
pituitary hormones in teleost fish with emphasis on gonadotropins |
publishDate |
1979 |
url |
http://collections.mun.ca/cdm/ref/collection/theses2/id/215384 |
long_lat |
ENVELOPE(-19.455,-19.455,65.656,65.656) |
geographic |
Keta |
geographic_facet |
Keta |
genre |
Newfoundland studies University of Newfoundland |
genre_facet |
Newfoundland studies University of Newfoundland |
op_source |
Paper copy kept in the Centre for Newfoundland Studies, Memorial University Libraries |
op_relation |
Electronic Theses and Dissertations (34.80 MB) -- http://collections.mun.ca/PDFs/theses/Ng_TziBun.pdf 75062059 http://collections.mun.ca/cdm/ref/collection/theses2/id/215384 |
op_rights |
The author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission. |
_version_ |
1766112976658497536 |