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Chehade C, Amaral FG, Branco GS, Cassel M, De Jesus LWO, Costa FG, Bordin SA, Moreira RG, Borella MI. Molecular characterization of different preproGnRHs in Astyanax altiparanae (Characiformes): Effects of GnRH on female reproduction. Mol Reprod Dev 2020; 87:720-734. [PMID: 32418283 DOI: 10.1002/mrd.23351] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 05/03/2020] [Indexed: 12/13/2022]
Abstract
Gonadotropin-releasing hormone (GnRH) is a key molecule in the initiation of the hypothalamic-pituitary-gonadal axis. Thus, knowledge about GnRH may contribute to the effectiveness of species reproduction. Using a Neotropical tetra Astyanax altiparanae as a fish model species, the GnRH forms were characterized at the molecular level and the role of injected GnRHs in vivo was evaluated. The full-length complementary DNA (cDNA) sequences of preproGnRH2 (612 bp) and preproGnRH3 (407 bp) of A. altiparanae were obtained, and the GnRH1 form was not detected. The cDNA sequences of preproGnRH2 and preproGnRH3 were found to be conserved, but a change in the amino acid at position 8 of the GnRH3 decapeptide of A. altiparanae was observed. All the injected GnRHs stimulated lhβ messenger RNA (mRNA) expression but not fshβ mRNA expression, and only GnRH2 was able to increase maturation-inducing steroid (MIS) levels and possibly stimulate oocyte release. Furthermore, only GnRH2 was able to start the entire reproductive hormonal cascade and induce spawning.
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Affiliation(s)
- Chayrra Chehade
- Fish Endocrinology Laboratory, Department of Cell and Developmental Biology, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Fernanda G Amaral
- Department of Physiology and Biophysics, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, São Paulo, Brazil.,Department of Physiology, Federal University of São Paulo (UNIFESP), São Paulo, São Paulo, Brazil
| | - Giovana S Branco
- Fish Endocrinology Laboratory, Department of Cell and Developmental Biology, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, Brazil
| | - Mônica Cassel
- Department of Education - Bachelor of Science in Animal Science, Mato Grosso Federal Institute of Education, Science, and Technology (IFMT)-Alta Floresta Campus, Alta Floresta, Mato Grosso, Brazil
| | - Lázaro W O De Jesus
- Laboratory of Applied Animal Morphophysiology, Department of Histology and Embryology, Institute of Biological Sciences and Health, Federal University of Alagoas (UFAL), Maceio, Alagoas, Brazil
| | - Fabiano G Costa
- Department of Biological Sciences, State University of Northern Paraná (UENP), Jacarezinho, Paraná, Brazil
| | - Silvana A Bordin
- Department of Physiology and Biophysics, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, São Paulo, Brazil
| | - Renata G Moreira
- Laboratory of Metabolism and Reproduction of Aquatic Organisms, Department of Physiology, Institute of Biosciences, University of São Paulo (USP), São Paulo, São Paulo, Brazil
| | - Maria I Borella
- Fish Endocrinology Laboratory, Department of Cell and Developmental Biology, Biomedical Sciences Institute, University of São Paulo (USP), São Paulo, Brazil
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Abstract
This work deals with a family of neuropeptides, gonadotropin-releasing hormone (GnRH), that play a key role in the development and maintenance of reproductive function in vertebrates. 2. Until now, a total of 16 GnRH structural variants have been isolated and characterized from vertebrate and protochordate nervous tissue. All vertebrate species already investigated have at least two GnRH forms coexisting in the central nervous system. However, it is now well accepted that three forms of GnRH in early and late evolved bony fishes are present. 3. In these cases, cGnRH-II is expressed by midbrain neurons, a species-specific GnRH is present mainly in the preoptic area and the hypothalamus, and sGnRH is localized in the terminal nerve ganglion (TNG). In this context it is possible to think that three GnRH forms and three GnRH receptor (GnRH-R) subtypes are expressed in the central nervous system of a given species. 4. Then it is possible to propose three different GnRH lineages expressed by distinct brain areas in vertebrates: (1) the conserved cGnRH-II or mesencephalic lineage; or (2) the hypothalamic or "releasing" lineage whose primary structure has diverged by point mutations (mGnRH and its orthologous forms: hrGnRH, wfGnRH, cfGnRH, sbGnRH, and pjGnRH); and (3) the telencephalic sGnRH form. Also different GnRH nomenclatures are discussed.
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Affiliation(s)
- Gustavo M Somoza
- Laboratorio de Ictiofisiología, Instituto Tecnológico, Universidad Nacional de General San Martín, Chascomús, Buenos Aires, Argentina.
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Somoza GM, Lescheid DW, Miranda LA, Lo Nostro FL, Magliulo-Cepriano L, Montaner AD, Schreibman MP, Rivier JE, Sherwood NM. Expression of pejerrey gonadotropin-releasing hormone in three orders of fish. Biol Reprod 2002; 67:1864-71. [PMID: 12444064 DOI: 10.1095/biolreprod.102.004572] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Molecular variants of GnRH were characterized by reverse-phase, high-performance liquid chromatography from brain extracts of fish in three different orders: Synbranchiformes (swamp eel [Synbranchus marmoratus]), Cyprinidontiformes (platyfish [Xiphophorus maculatus] and green swordtail [X. helleri]), and Atheriniformes (Patagonia pejerrey [Odontesthes hatchery]). Also, pituitary gland extracts from the pejerrey O. bonariensis (Atheriniformes) were characterized. Eluted fractions were tested in radioimmunoassays with antisera specific to GnRH, including both antisera that detected only one form of GnRH and those that detected several forms. The results show that brain extracts obtained from all species contained the same three molecular forms of GnRH, which were immunologically and chromatographically undistinguishable from chicken GnRH-II, pejerrey GnRH (pjGnRH), and salmon GnRH. This study supports the hypothesis that expression of these three forms is common in different fish orders and that pjGnRH is the main regulator of pituitary function in these fish.
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Affiliation(s)
- G M Somoza
- Instituto Tecnológico de Chascomús (IIB-INTECH, CONICET-Universidad de San Martín), Camino de Circunvalación Laguna, Km 6. CC 164 (B7130IWA) Chascomús, Provincia de Buenos Aires, Argentina.
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Montaner AD, Park MK, Fischer WH, Craig AG, Chang JP, Somoza GM, Rivier JE, Sherwood NM. Primary structure of a novel gonadotropin-releasing hormone in the brain of a teleost, Pejerrey. Endocrinology 2001; 142:1453-60. [PMID: 11250925 DOI: 10.1210/endo.142.4.8077] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The neuropeptide GnRH is the major regulator of reproduction in vertebrates acting as a first signal from the hypothalamus to pituitary gonadotropes. Three GnRH molecular variants were detected in the brain of a fish, pejerrey (Odontesthes bonariensis), using chromatographic and immunological methods. The present study shows that one form is identical to chicken GnRH-II (sequence analysis and mass spectrometry) and the second one is immunologically and chromatographically similar to salmon GnRH. The third form was proven to be a novel form of GnRH by isolating the peptide from the brain and determining its primary structure by chemical sequencing and mass spectrometry. The sequence of the novel pejerrey GnRH is pGlu-His-Trp-Ser-Phe-Gly-Leu-Ser-Pro-Gly-NH(2), which is different from the known forms of the vertebrate and protochordate GnRH family. The new form of GnRH is biologically active in releasing gonadotropin and GH from pituitary cells in an in vitro assay.
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Affiliation(s)
- A D Montaner
- Instituto de Investigaciones Biomédicas, Fundación Pablo Cassará, Saladillo 2452 (C1440FFX), Buenos Aires, Argentina
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Montaner AD, Gonzalez O, Paz DA, Affanni JM, Somoza GM. Gonadotropin-releasing hormone (GnRH) variants in a lizard brain: is mammalian GnRH being expressed? Gen Comp Endocrinol 2000; 119:121-31. [PMID: 10936032 DOI: 10.1006/gcen.2000.7488] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In reptiles as in other vertebrates, multiple forms of gonadotropin-releasing hormone (GnRH) within a single brain have been identified. In this group the following GnRH molecular variants have been characterized either by direct or indirect methods: chicken GnRH I (cGnRH-I), chicken GnRH II (cGnRH-II), salmon GnRH (sGnRH) and several unidentified GnRH-like forms. In the present study GnRH variants were investigated in brain extracts of the lizard Tupinambis teguixin (= T. merinae) by combining high-performance liquid chromatography (RP-HPLC) followed by radioimmunoassays (RIA). Two peaks showing GnRH immunoreactivity with the elution position of synthetic mammalian GnRH (mGnRH) and cGnRH-II were detected. Both peaks were further analyzed with different radioimmunoassay systems specific for mGnRH, cGnRH-I, and cGnRH-II. Pooled fractions corresponding to the first eluting peak showed no crossreactivity when analyzed with a cGnRH-I specific assay and logit-log displacement curves were not significantly different from those of synthetic mGnRH with homologous RIA systems. The second peak showed immunological characteristics of cGnRH-II when analyzed with a specific antiserum. The first ir-GnRH peak was selected for further RP-HPLC purification showing similar chromatographic behavior as mGnRH synthetic standard. We demonstrated the absence of cGnRH-I in this lizard using well-characterized antisera.
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Affiliation(s)
- A D Montaner
- INEUCI-CONICET, Universidad de Buenos Aires, Buenos Aires, 1428, Argentina
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Yahalom D, Chen A, Ben-Aroya N, Rahimipour S, Kaganovsky E, Okon E, Fridkin M, Koch Y. The gonadotropin-releasing hormone family of neuropeptides in the brain of human, bovine and rat: identification of a third isoform. FEBS Lett 1999; 463:289-94. [PMID: 10606740 DOI: 10.1016/s0014-5793(99)01638-5] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The mammalian gonadotropin-releasing hormone (GnRH-I), which regulates reproduction, was the first isoform of GnRH that was identified in mammals. Recently, we and others have demonstrated the existence of a second isoform of GnRH in the brain of mammals. The presence of a third isoform of GnRH, GnRH-III, in the brain of mammals is reported herein. GnRH-III, extracted from the brain of bovine and human, was purified by high performance liquid chromatography, using two distinct elution programs. In both, GnRH-III was eluted at the same positions as synthetic salmon GnRH, as demonstrated by radioimmunoassay. The luteinizing hormone-releasing activity of purified GnRH-III, using dispersed rat pituitary cells, was found to be similar to that of synthetic salmon GnRH. The total amount of GnRH-III, determined by radioimmunoassay, in the hypothalamus and midbrain of humans and calves is similar to that of GnRH-I. Immunohistochemical studies demonstrated GnRH-III-containing neurons in the hypothalamus and midbrain of human and GnRH-III fibers in the median eminence of rats. The distribution of GnRH-III in the brain suggests that in addition to a putative function as a neurohormone at the hypothalamic-pituitary axis, GnRH-III may have other functions. Our present results suggest that multiple isoforms of GnRH are present in the brain of mammals, and further studies are required in order to elucidate their biological functions.
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Affiliation(s)
- D Yahalom
- Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel
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Rodríguez-Gómez FJ, Rendón MC, Sarasquete C, Muñoz-Cueto JA. Distribution of gonadotropin-releasing hormone immunoreactive systems in the brain of the Senegalese sole, Solea senegalensis. Histochem J 1999; 31:695-703. [PMID: 10646833 DOI: 10.1023/a:1003917913297] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The present paper reports the immunohistochemical distribution of the gonadotropin-releasing hormone (GnRH) structures in the brain of the Senegalese sole, Solea senegalensis. In this study, we have used two antibodies against the salmon GnRH and chicken GnRH-II forms and the streptavidin-biotin-peroxidase complex method. Immunoreactive cell bodies are observed at the junction between the olfactory bulbs and the telencephalon (terminal nerve ganglion cells), in the ventral telencephalon, in the preoptic parvocellular nucleus, and in the synencephalic nucleus of the medial longitudinal fasciculus. GnRH-immunoreactive fibres were found extensively throughout the brain, located in the telencephalon, preoptic area, hypothalamus, hypophysis, optic tectum, midbrain and rhombencephalon. The antisera used in this study against the two GnRH forms exhibited cross-reactivity on the same cell masses and did not allow cell populations expressing different GnRH forms to be discriminated clearly. However, anti-salmon GnRH immunostained the GnRH cells and fibres of the forebrain much more intensely, whereas the anti-chicken GnRH antiserum shows a higher immunoreactivity on synencephalic cells of the medial longitudinal fasciculus.
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Affiliation(s)
- F J Rodríguez-Gómez
- Department of Animal Biology, Plant Biology and Ecology, Faculty of Marine Sciences, University of Cádiz, Spain
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Montaner AD, Affanni JM, King JA, Bianchini JJ, Tonarelli G, Somoza GM. Differential distribution of gonadotropin-releasing hormone variants in the brain of Hydrochaeris hydrochaeris (Mammalia, Rodentia). Cell Mol Neurobiol 1999; 19:635-51. [PMID: 10384261 DOI: 10.1023/a:1006936619129] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
1. In a previous paper we reported evidence for the presence of mGnRH- and sGnRH-like peptides in the preoptic-hypothalamic region of the capybara Hydrochaeris hydrochaeris (Montaner et al., 1998). In that study, the presence of a cGnRH-II like molecule in olfactory bulb extracts was suggested. 2. The capybara, the largest living rodent in the world, belongs to the order Hystricomorpha, which is considered to be one of the oldest groups of rodents. Some authors consider that this group is the ancestor of all remaining rodents. 3. In this study we have characterized GnRH molecular variants found in extracts from the olfactory bulbs and the mesencephalic region of capybara. These regions represent the two GnRH neuronal systems: the terminal nerve-septopreoptic and the midbrain systems. 4. An indirect method combining reverse-phase high-performance liquid chromatography (RP-HPLC) and radioimmunoassay (RIA) was used to characterize GnRH variants. The analysis of both extracts with two different RIA systems revealed three immunoreactive GnRH peaks, coeluting with mGnRH, cIIGnRH, and sGnRH synthetic standards. These results were additionally supported by serial dilution studies with specific antisera. 5. To our knowledge this the first report on the presence of three GnRH variants in the brain of an eutherian mammal. These results suggest that, similarly to other vertebrates, the expression of multiple GnRH variants may also be a common pattern in mammals.
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Affiliation(s)
- A D Montaner
- Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (UBA), Argentina
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Montaner AD, Somoza GM, King JA, Bianchini JJ, Bolis CG, Affanni JM. Chromatographic and immunological identification of GnRH (gonadotropin-releasing hormone) variants. Occurrence of mammalian and a salmon-like GnRH in the forebrain of an eutherian mammal: Hydrochaeris hydrochaeris (Mammalia, Rodentia). Regul Pept 1998; 73:197-204. [PMID: 9556083 DOI: 10.1016/s0167-0115(98)00005-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The molecular variants of Gonadotropin releasing hormone (GnRH) in brain extracts of the eutherian mammal Hydrochaeris hydrochaeris (Mammalia, Rodentia) were characterized. An indirect method combining reverse-phase high-performance liquid chromatography (RP-HPLC) and radioimmunoassay (RIA) with different antisera was used. Two different forebrain regions (olfactory bulbs and preoptic-hypothalamic region) were analyzed. Characterization of RP-HPLC fractions from preoptic-hypothalamic extracts with three different RIA systems revealed two immunoreactive GnRH (ir-GnRH) peaks coeluting with mammalian GnRH (mGnRH) and salmon GnRH (sGnRH) synthetic standards. These results were additionally supported by serial dilution studies with specific antisera. Similar results were obtained from olfactory bulb extracts with the same methodology. However, a third ir-GnRH peak in a similar position to that of chicken GnRH II (cIIGnRH) synthetic standard was revealed. As far as we know, this is the first report showing chromatographic and immunological evidences for the presence of a second GnRH variant in the forebrain of an eutherian mammal.
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Affiliation(s)
- A D Montaner
- Instituto de Neurociencia (INEUCI-CONICET), Departamento de Biología, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina
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Stefano AV, Canosa LF, D'Eramo JL, Fridman O, Affanni JM, Somoza GM. GnRH molecular variants in the brain and pituitary gland of pejerrey, Odontesthes bonariensis (Atheriniformes). Immunological and chromatographic evidence for the presence of a novel molecular variant. Comp Biochem Physiol C Pharmacol Toxicol Endocrinol 1997; 118:335-45. [PMID: 9467885 DOI: 10.1016/s0742-8413(97)00135-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Gonadotropin-releasing hormone (GnRH) molecular variants in the brain and pituitary gland of pejerrey, Odontesthes bonariensis (Atheriniformes), were characterized by gradient reverse phase high performance liquid chromatography (RP-HPLC). Eluted fractions were tested in radioimmunoassays with different antisera. The results show that the brain extract contains three forms of GnRH: one is immunologically and chromatographically similar to cIIGnRH (chicken II), and another is similar to sGnRH (salmon). A third GnRH appears to be chromatographic and immunologically different from the nine other known forms of the vertebrate hormone. This is the only variant present in the pituitary gland.
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Affiliation(s)
- A V Stefano
- Instituto de Neurociencia (INEUCI-CONICET), Buenos Aires, Argentina
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Powell JF, Standen EM, Carolsfeld J, Borella MI, Gazola R, Fischer WH, Park M, Craig AG, Warby CM, Rivier JE, Val-Sella MV, Sherwood NM. Primary structure of three forms of gonadotropin-releasing hormone (GnRH) from the pacu brain. Regul Pept 1997; 68:189-95. [PMID: 9100286 DOI: 10.1016/s0167-0115(96)02119-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Perchlike fish are a vast group of advanced teleosts. The species examined to date have three forms of gonadotropin-releasing hormone (GnRH) within a single species, but the origin of the third GnRH peptide is unknown. In this study, the primary structure of three GnRH peptides is determined from the brain of the pacu, Piaractus mesopotamicus, an example of a teleost that is less advanced than the perchlike fish. The GnRH was purified from pacu brain extracts using high performance liquid chromatography (HPLC) and radioimmunoassay (RIA). The three forms identified by chemical sequencing and mass spectrometry are sea bream GnRH (pGlu-His-Trip-Ser-Tyr-Gly-Leu-Ser -Pro-Gly-NH2, 1113.4 Da); chicken GnRH-II (pGlu-His-Trp-Ser-His-Gly-Trp-Tyr-Pro-Gly-NH2, 1236.6 Da); and salmon GnRH (pGlu-His-Trp-Ser-Tyr-Gly-Trp-Leu-Pro-Gly-NH2, 1212.3 Da). In addition the number of forms of GnRH in the brains of male and female fish was determined separately. The same three forms of GnRH were present in the brains of both sexes as determined by antisera cross-reactivity and elution position from the HPLC column. The results indicate that the pacu brain has the identical forms of GnRH identified in perchlike fish and hence, the origin of three forms occurred earlier in evolution than previously thought.
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Affiliation(s)
- J F Powell
- Department of Biology, University of Victoria, B.C., Canada
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Somoza GM, Paz DA, Stefano AV, Affanni JM. Identification of immunoreactive mammalian gonadotropin-releasing hormone in the brain of metamorphic larvae of Bufo arenarum Hensel (Amphibia: Anura). Int J Dev Neurosci 1996; 14:663-72. [PMID: 8930698 DOI: 10.1016/0736-5748(95)00102-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Gonadotropin-releasing hormone (GnRH) immunoreactivity in brain extracts of Bufo arenarum tadpoles were investigated by high-performance liquid chromatography, followed by radioimmunoassay analysis using two different antisera raised against different GnRH variants. Only one immunoreactive peak was identified, eluting in the same position as synthetic mammalian GnRH. This result was further confirmed by serial dilution studies using more specific mammalian GnRH antisera. Our results suggest that mammalian GnRH is most likely an endogenous peptide in the brain of the developing larvae and froglets of Bufo arenarum and quite likely it is the only GnRH variant present during those development stages. The distribution and density of cell bodies and fibers were analysed by immunocytochemical procedures. Immunoreactive cell bodies appeared in the olfactory epithelium and across the olfactory nerve at late prometamorphic larval stages. Near the metamorphic climax and in froglets, perikarya and fibers were detected in basal forebrain, preoptic and hypothalamic areas. No immunoreaction was observed at midbrain, hindbrain and spinal cord levels. This study suggests that mammalian GnRH is most likely an endogenous peptide and is probably the only GnRH variant in the brain of the developing larvae and froglets of Bufo arenarum.
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Affiliation(s)
- G M Somoza
- INEUCI-CONICET, Departamento de Biología, Facultad de Ciencias Exactas y Naturales, Buenos Aires, Argentina.
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D'Eramo JL, Somoza GM, Stefano A, Canosa LF, Fridman O. Rapid separation of gonadotropin-releasing hormone molecular forms by isocratic high-performance liquid chromatography on an ion-exchange column. J Chromatogr B Biomed Appl 1996; 682:219-24. [PMID: 8844413 DOI: 10.1016/0378-4347(96)00087-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The purpose of the present work was to develop a chromatographic system for the separation of five molecular forms of the gonadotropin-releasing hormone (GnRH); mammalian GnRH (mGnRH) (LHRH), salmon GnRH (sGnRH), chicken I GnRH (cIGnRH), chicken II GnRH (cIIGnRH) and lamprey GnRH I (IGnRH-I). By using an ion-exchange HPLC column and isocratic elution, it was possible to separate properly the five peptides in approximately 20 min. The utility of the system in determining the GnRHs forms present in the brain of two species of vertebrates was examined.
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Affiliation(s)
- J L D'Eramo
- Laboratorio de Endocrinología Comparada, Fundación Centro de Investigaciones Médicas Albert Einstein, Buenos Aires, Argentina
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Andersson E, Bogerd J, Borg B, Sharp PJ, Sherwood NM, Goos HJT. Characterization and localization of gonadotropin-releasing hormone in the brain and pituitary of the three-spined stickleback, Gasterosteus aculeatus. Cell Tissue Res 1995. [DOI: 10.1007/bf00318162] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Powell JF, Zohar Y, Elizur A, Park M, Fischer WH, Craig AG, Rivier JE, Lovejoy DA, Sherwood NM. Three forms of gonadotropin-releasing hormone characterized from brains of one species. Proc Natl Acad Sci U S A 1994; 91:12081-5. [PMID: 7991588 PMCID: PMC45380 DOI: 10.1073/pnas.91.25.12081] [Citation(s) in RCA: 168] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Most vertebrate species have more than one form of gonadotropin-releasing hormone (GnRH) in their brains, but it is not clear whether each form has a distinct function. We report that sea bream (Sparus aurata) brains have three forms of GnRH, one of which is described herein and is called sea bream GnRH (sbGnRH). The primary structures of two forms were determined by Edman degradation and mass spectral analysis. The amino acid sequence of sbGnRH is pGlu-His-Trp-Ser-Tyr-Gly-Leu-Ser-Pro-Gly-NH2. The second peptide is identical to a form originally isolated from chicken brains (cGnRH-II): pGlu-His-Trp-Ser-His-Gly-Trp-Tyr-Pro-Gly-NH2. cGnRH-II is the most ancient form of GnRH identified to date in jawed fish and the most prevalent form throughout the vertebrates. The third form of GnRH has previously been identified as salmon GnRH by cDNA studies and is confirmed here by chromatographic and immunological studies. Phylogenetic distribution of GnRH peptides suggests sbGnRH arose in the perch-like fish as a gene duplication of the existing cGnRH-II or salmon GnRH genes. All three identified GnRH peptides were synthesized and shown to release gonadotropin in vivo in the sea bream. The dominant form of GnRH stored in the pituitary was sbGnRH. Not only was the content of sbGnRH 500-fold greater than that of salmon GnRH but also cGnRH-II was not detected in the pituitary. The latter evidence suggests that sbGnRH is the endogenous releaser of gonadotropin II.
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Affiliation(s)
- J F Powell
- Department of Biology, University of Victoria, B.C. Canada
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